Boating safety includes proper operation, obeying rules and regulations, and having the right safety equipment on board. The first two are things YOU have to to learn and be willing and able to perform correctly before operating a boat yourself. The right safety equipment is specified by USCG regulations and boats operated in regulated waters MUST carry the required safety equipment. Boats operated on non-regulated waters, usually small lakes and rivers, SHOULD carry the same safety equipment and local laws may require it. Not having the prescribed safety equipment could subject you to significant fines if your boat gets inspected by law enforcement and costly liabilities if you are involved in an accident and didn't have the required, up to date safety items on board at the time. Of course, just having the right equipment isn't enough -- you (and everyone on your boat) needs to know where it is located, how to get it out and how to use it.
Learning proper operation of your boat usually involves more than a few minutes of instruction by the dealer or person you purchase (or rent) your boat from. Ideally you should have hands-on training by a qualified instructor. In some cases, such as piloting commercial boats, you must have a Captain's License that has minimum training and testing requirements. If your boat is for personal use you won't need the License, but you should still ensure you are qualified to operate your boat before you take it out on the water without a more experienced skipper on board. The training you need will depend on what type of boat you are in. Personal boats, such as canoes, kayaks, and row boats are pretty simple but you still need to know how to use them safely. That would include how to launch them, how to load them, how for you and any passengers to sit safely, and how to paddle them, steer them stop them and dock them. Motor boats will require additional instruction on how to operate the controls along with guidance on choosing a safe speed and other operational considerations, depending on where you are. Sail boats will require you to know points of sail and how to raise, lower, and adjust the sails. Many sailboats also have auxiliary power which you will also need to know how to use. Operating any boat without proper training is a recipe for disaster, for you and anyone around you! For personal use you may be able to get training from a friend or associate who is an experienced, competent boater. Make sure you are understand and are comfortable with all the aspects of operating a boat before you attempt to do so on you own. Waves are almost a constant feature you need to know how to handle. In general it is best to cross waves perpendicular to their shape. Letting one strike the side of your boat will cause it to rock and if it is big enough may make it capsize. The same applies to the wake kicked up by other boats. Low waves and small wakes are not usually of any concern, but as the grow bigger they can wreak havoc. I was once towing a water skier when a harbor tour boat came by kicking up a 2' wake. My skier caught the tip of his ski in the wake and it flipped and spun him like a top!
Certain navigation and other lights are required on any boat used after dark. Standard navigation lights include a red light visible from the port side, a green light visible from the starboard side, and white lights front and rear. In addition all boats need to display a white light visible all around when moored or at anchor outside a designated moorage at night. Sailboats also have to display a white light visible from the front when using an auxiliary motor at night. Lighting requirements might be different for different sized boats as well as different between power and sailboats. Check to make sure your boat has all the required lights for its type and size. Modern LED lights take a lot less power than the old incandesent lights. This is particularly helpful for anchor lights or other lights that will be used while you are on battery only power.
Day shapes are used on sailboats to let other boaters know if the sailboat is under power or at anchor. The use of day shapes on inland waters seems to be often neglected, which is a sad thing as it may contribute to unnecessary accidents or close calls. A sailboat under power should display a black ball shape. At anchor in daylight hours they should display a black, inverted cone shape. There are other shapes such as diamonds and combinations of shapes used on commercial fishing vessels and vessels under tow but you seldom see them on personal boats. The day shapes are always black because other colors can not always be distinguished if the sun is in your eyes. Day shapes are required on vessels over 20m in length and recommended for all vessels and are typically displayed in the fore triangle (e.g., hung from the forestay).
Rules and regulations will, to some extent, depend on where you are using your boat. Regulated waters usually include all coastal waters and large, navigable lakes and rivers like the Great Lakes, the St Lawrence seaway and the Mississippi River. The regulations governing these waters include federal laws and regulations put forth by the U.S. Coast Guard. There are other local rules and regulations that govern recreational boating on lakes and rivers. It is your responsibility to learn the laws, rules, and regulations pertaining to whatever venue you are operating in. Failure to do so could result in serious accidents or expensive fines. You will find speed limits and restricted areas posted near most boat docks, launch ramps, swimming areas, brides, and dams in both regulated and unregulated waters. Obeying these rules is both your legal obligation and a matter of common courtesy.
Safety equipment requirements are primarily based on US Coast Guard regulations. In pretty much all cases you are required to have personal flotation devices (i.e, life vests) readily available and accessible to every person on a boat. As boats get larger they are required to have additional throwable flotation devices (specially designed cushions or life preservers). All boats are required to carry visible and audible signalling devices. In regulated waters you are required to carry signal flares. Boats operated after dark require navigation lights. All boat having motors must carry at least one fire extinguisher. Boats over 25' must carry at least 2 fire extinguishers. All safety equipment should be up to date and easily accessible by the crew. Everyone on board, especially crew members, should know what and where every piece of safety equipment is and how to use it.
Signal flares come in several forms. There are hand held flares and flare guns. Flare guns shot the flare high into the air so it can be seen from long distances. Hand held flares can only be seen by people with a direct line of sight to where you are. Hand held flares are probably adequate for use on inland lakes and rivers but I would want to have a flare gun if I were doing any off-shore, blue water voyaging. Signal flares are not cheap and they come with an expiration date. Some expired flares might still work, but do you want to bet your life on that? I don't! Expired flares do not meet USCG regulations so having expired flares might result in a stiff fine, not to mention they very well might fail when you need them most!
Having the required safety equipment on board is just the first step. Obviously you must also know where to find it and how to use it! Even simple items like life vests require a certain expertise to be worn correctly. Putting one on wrong could cost you your life! Throwable cushions are pretty simple to use but it is advisable that you practice throwing them so you will be able to get them where you need them if someone falls overboard and needs help. Know how to ignite or shoot your flares. You should not fire flare guns as practice, except in an official USCG designated flare practice area. Any passing aircraft that sees a flare is obligated to report it which would launch a possibly expensive search operation. Audible signals (horns and whistles) have specific meanings you need to know. They are generally divided into short and long blasts. Short blast is 1 second. A long blast is 4-6 seconds. One short blast is used by boats approaching each other to signal they are passing on the port (left) side. Two short blasts mean passing on the starboard (right side). By the way, the generally accepted practice is to pass port to port. Three short blasts means your engine is in reverse. Five short blasts mean danger or I do not understand or agree with your signal. You might use 5 blasts to warn an approaching boat that you have a swimmer in the water on the side he intends to pass on or if there is some danger such as rocks or debris or another boat there. Audible signals are also used in times of reduced visibility, such as fog or around blind turns. One long blast means entering or exiting a blind turn, nearing an obstructed area, or leaving a dock or berth. One long blast every two minutes is used by power boats operating in low or restricted visibility, One long blast followed by two short blast is used by boats under sail operating in low or restricted visibility. Whey would power and sail boats use different signals for the same situation? Well, sailboats may not be able to change course or speed as quickly as power boats. Knowing a sailboat is approaching in limited visibility conditions lets you prepare to allow more time for evasive maneuvers if they are needed. It may also help that you know you will not be able to listen for approaching engine noise and that the other boat could appear out of the fog without you ever hearing the sound of their engine.
EPIRBs (Emergency Position Indicating Radio Beacons) are required on large boats (typically over 300 tons) but might be useful on smaller craft if you are sailing off-shore. They send an SOS signal that includes your precise coordinates to assist rescuers in finding you. They are somewhat large and expensive. A Personal Locator Beacon (PLB) performs a similar function. They are small enough to carry in your pocket (they are designed for hikers) and start at prices much less than EPIRBs. Emergency beacons are probably not needed on inland waters but I wouldn't want to do any ocean voyaging without one. You might want to have a PLB you can use both on land at and sea, for hiking, riding OHVs or horses, hiking, boating, etc. Most PLBs are waterproof down to at least a couple of meters.
There are no laws or regulations I know of that specify proper clothing for boating, other than perhaps laws regarding public nudity. However, to be safe and comfortable you should dress appropriately when boating. Avoid exceedingly loose clothing that might get caught on parts of the boat. For both your own safety and to protect the deck of the boat, wear soft-soled shoes with a good grip. "Real" boaters wear deck shoes when on the boat and do not wear them off the boat where they could pick up bits of debris that would damage the deck. Slick or loose shoes may cause you to slip and fall, perhaps even fall overboard! Wearing any shore worn shoes on your boat risks damaging the surface of your deck. It is popular to wear swimsuits or shorts when boating but be aware you may be exposing your skin to excessive UV radiation which could lead to sunburn and eventually even to skin cancer. You will get exposed to sunlight reflected off the water as well as from directly overhead. Wear sunblock on exposed skin. A good broad-brimmed hat or at least one that shades our eyes will be helpful. Your eyes will also need protection from both direct and reflected sunlight so a good pair of sunglasses is advised. Most tasks on a power boat don't require gloves, but many tasks on a sailboat or any kind of paddle boat will require gloves to protect your hands from blisters, rope burns, and other injuries.
If your boat is on a trailer you will need to have safe towing skills and learn how to launch the boat. To launch the boat back the trailer down the launch ramp until the boat is in the water. If you can't get it far enough down the ramp before the water is high enough to get the brakes on your tow vehicle wet you might need a hitch or tongue extension to give you further reach. Boat trailer guides are really useful when backing the empty trailer into the water to retrieve the boat and they also make it easier to align the boat to the trailer. When towing a boat, always make sure the boat is securely attached to the trailer and that the trailer hitch, safety chains, wiring, lights, and brakes are working properly. When towing you usually need to travel slower than you do without a trailer and give yourself more room for turning and stopping. Trailers can also be affected by wind or gusts from passing trucks and buses.
You will need to know how to safely move your boat out of its slip and how to dock it again when you return. There are many Youtube videos that can teach you useful techniques. In general you need to make sure you have untied all dock lines and made sure the lane you are entering is clear of other boats. When returning, approach the slip/dock slowly, have your boat hook ready to help guide you into the slip, and have your docking lines ready to secure the boat once you are in place. There are techniques that use spring lines to help position the boat and stop it when docking, but not all boats have spring lines. Speed in any marina or anchorage is always limited. You usually only run the motor at idle when docking. Boat trailer guide posts are useful for positioning your trailer and aligning the boat to the trailer.
Once you are out on the water you need to maintain situational awareness. That means you need to be constantly looking around you, watching for other boats, swimmers, obstacles, or even disturbances on the water that might indicate a problem. Adjust your behavior depending on what you see around you. Watch your speed. There aren't a lot of speed limits on the open water, but there are definitely speed limits near marinas, boat ramps, swimming areas, bridges, dams, and other points of interest. You should also slow down whenever there are other boats near by, to give yourself time to react if one of them suddenly darts into your path. In general power boats are expected to yield the right of way to sailboats but if you are in a sailboat, don't count on it! If you are in a power boat, do your best to comply. Boats should pass each other "port to port" (i.e., left side to left side). Think of it like two cars going opposite directions on the highway. By the way, you can remember that "port"is the left side because both words have 4 letters. The right side of a boat is called "starboard". The port side is so named because that was the side boats usually docked on in port. Starboard is thought to have come from "steerboard" at a time before boats had rudders and were steered by a board usually from the right hand side as the one steering the boat faced forward.
Passenger safety should be one of your primary concerns. Perhaps your first option is to make sure your passengers are capable of following safety protocols and looking after themselves. During one of our sailboat outings we witnessed a power boat accident in which an elderly lady fell overboard. They got her out of the water quickly but she apparently had a heart attack and even CPR by the local fire department medics couldn't save her. Ironically, she didn't like going out on a boat in the first place and her family had talked her into it. Always show passengers where all the safety equipment is located and how and when to use it. Make sure children and other possible at risk passengers ALWAYS wear their live jackets. Avoid carrying passengers who are intoxicated or under the influence of drugs, even prescription drugs if the drug affects their senses and/or reaction time. Try to keep an eye on your passengers and advise them if/when they are doing anything that might put them or anyone else at risk. If all else fails and your passengers do not cooperate, head back and park the boat and ask them to disembark. Going back and/or asking people to leave may dampen spirits but not as badly as someone getting hurt!
Be safe and have fun!