Some good advice about the details of preparation
In Time of Peace, Prepare for...
But what to do?
First, have a plan.
Second, dry-run the execution to your plan and talk to the other people who will be involved in helping you with your plan.
Third, give your plan to your insurance agent and ask for his recommendations.
Fourth, have all extra line, fenders, chafe gear, extra jack stands and equipment you might need in place either on your boat or in some easy-to-access place, so all you have to do is pick it up.
Fifth, decide when you are going to put your plan into effect -- i.e., sooner rather than later.
Sixth, never stay on the boat.
In Stamford, CT where many of the BoatTEST.com staffers boat, the owners of large yachts plan to get behind a 25' Corps of Army Engineers Hurricane doors and barrier. The barrier keeps downtown Stamford from being flooded by Long Island Sound and thankfully hundreds of boats can get behind the barrier.
If your boat is trailerable, by all means take it out of the water to high ground. Small boats, and high-performance boats with low freeboard are particularly vulnerable, even if they have self-draining cockpits. These type boats almost always become submerged from storm surge, rain, or waves. Don't count on your small bilge pump and long battery life.
If your boat is large, make arrangements far in advance to have it hauled and supported by extra jack stands, or tie your boat down to the pavement if at all possible.
Remember, storm surge causes more problems than the wind and rain. Hurricanes almost always come with a high moon tide, so you can have water 10' to 20' higher than normal. If your location is in the spout of a funnel of water -- such as the upper Chesapeake Bay or the west end of Long Island Sound -- you are particularly vulnerable to high water on the second high tide.
For a superb article on how to prepare your boat for a hurricane, complete with detail drawings about how to tie up your boat, go to Boat/U.S.'s website. Click here. http://www.boatus.com/hurricanes/HurricaneWarning.pdf