If you're not familiar with the "inflatable jeans" trick then learn it before heading out on your next marlin-fishing trip. This is a standard lifesaving tip used in Water Safety courses and can be learned in a few minutes of practice in a lake or deep pool. This is, however, a short-term survival technique to help you stay afloat and is no substitute for carrying a personal flotation device (PFD). It also won't overcome the disadvantage from immersion hypothermia, which is a great threat to sailors as well.
Remember, survival is about an attitude of preparedness. You have to plan for the unexpected. In sailing, more so than other outdoor activities, there are many unexpected and unplanned events that can befall you, particularly associated with the weather. You should have a quality life raft on your boat (and know how to deploy it), a de-salinator for procuring freshwater from the sea, a suit to contend with immersion hypothermia, and a reliable means of sending a distress signal.
I spoke with maritime survival expert Doug Ritter of www.equipped.org, who rigorously tests the latest gear in the industry. Doug's advice was don't leave home without the new McMurdo Fast Find Personal Location Beacon (PLB). "It is small enough to fit in a pocket and inexpensive enough that almost everyone who can afford to be at sea can afford it. I'd never be afloat without a PFD for floatation and a PLB to get myself rescued," said Ritter.
Talk to some experienced boaters to see what they carry on their person for your region and consider taking a boating safety course. Lastly, check out the book Adrift . It is the harrowing account of Steven Callahan's epic ordeal on the open ocean, where he endured 76 days afloat on a dinky, ill-equipped life raft in the Pacific after his boat capsized on a solo trip. After reading this you WILL think about being prepared for your next journey. Even if you are an inlander and don't venture out on the ocean, Callahan's story provides valuable lessons in improvisation and creative problem-solving.