On high-wind days, typically a sailor will concentrate solely on what's above the deck - i.e., sail size, proper rigging, sail handling during gusts, etc. But when sailing in winds of 25 knots and higher, the force of the wind against the board itself can mean the difference between a great session and crashing and burning. You've probably felt it at one time or another when carrying your board down to the water on a windy day: It's all you can do just to hang on. But you can harness that energy.
The same force that lifts your board out of control can be used to keep it in control. While sailing at planing speed, the front half of your board skims over the water and allows the wind to pass both under and over the hull, similar to the way air passes under and over the wing of an airplane. As the air flows over the top of the deck and under the bottom, it creates a low-pressure area above the deck and a high-pressure area below. If you're not careful, this force can lift the board into a tail walk and cause you to spin out. To keep in control, you've got to control the angle of attack to the wind. If the windward rail is higher than the leeward rail, the wind will lift the front of the board. But if the windward rail is lower, the wind will push the nose down. Keep the board in the water during the gusts by lifting with your toes in the foot strap and pressing your heel down. This will help get the board to "heel to windward," and the wind deflected off the deck will push down the front of the board, which keeps it firmly on the water. In lighter wind, point your toes and heel the board over to leeward to get the wind under the board. This will lift the hull slightly, producing less wetted surface and more speed. Experiment with heeling the board until you find the best angle of attack.