This is old news to most of you but this site has some good info
NOTE: Each rule is followed by a number of Case Histories - Real-life examples of close calls and fatalities.
1) Always Wear Your PFD
2) Always Dress For The Water Temperature
3) Field-Test Your Gear
4) Swim-Test Your Gear Every Time You Go Out
5) Imagine The Worst That Could Happen and Plan For It