Something I have been using a lot this winter and is simply the best piece of clothing I bought since the drysuit. Easy to put over everything and keep it dry and warm in the most gruelling of circumstances.
A good Personal Flotation Device can be a lifesaver, keep in mind that different weights need different PFD's.
The wetsuit, the cheapest way to keep your body warm in cold circumstances, not the most comfortable way though. I used it a lot in the beginning but now I prefer my paddle jacket and thermal undershirts in cold conditions.
When the circumstances require it, this suit has it all. You can stay dry and warm forever and when you need to tinkle, there is a handy extra zipper for it. The zipper on top isn't so easy to operate by yourself, but if you keep it greased up, it closes much easier. The name of this wonderful suit is drysuit code zero from the brand Gul.
Cheap, wonderfull things, never get cold hands again, even in the most dire conditions. Everybody should get a pair in my opinion.
Kayak boots come in all shapes and sizes but even the most cheapest pair keeps your feet warm.
In the summertime it is a lot easier to use a pair of ocean shoes or flipflops whenever it's easy going on the shore.