Always make sure that you wear a proper life jacket and that you know fully how to use it. Always make sure that the life jacket you are using also has a very high pitched and piercing whistle attached to it, so that if you do get into trouble, your call for help will be heard. Another thing to consider is taking with you a fully waterproof holdall where you can keep a dry change of clothes to keep you warm if the worst does happen. Also make sure that you always tell someone what time you intend to leave the shore and what time you intend to arrive back again at any particular location, so that if the worst does happen, someone can raise the alarm.
As with any waterbased activities, commonsense must prevail at all times. It is sadly all too often when commonsense flies out of the window that you increase exponentially the chances of having an accident whilst out on the water. Make sure you carry a mobile phone, keep the batteries and spares too fully charged up, the same goes for emergency contact devices such as a cb radio or walkie talkie. Even though one or two of these devices may seem a little old fashioned these days, they will all increase the chances of your messages being picked up by someone, somewhere if something does go wrong.
If going out on the open sea, remember that sea conditions can change extremely rapidly and too, there might be rip currents that you have no knowledge of. Good preparation in advance is key. Make sure that the craft you are using is suited to the water conditions you intend to use it upon. Do not overload your craft and also keep the weight evenly distributed. If you do run into difficulties, do not panic, this is often just about the worst thing you can do. Try to stay as calm as possible to make the most rational and clear thinking decisions that you can, this could mean the difference between life and death. Again, I'm going to reiterate and emphasize the point made at the beginning of this article, never, ever under estimate the power of water. Have respect for it at all times, be well prepared and there really is no reason why you shouldn't have lots of enjoyment upon it.