• To freeze someone zipping down the mountain, shutter priority is the way to go, with a shutter speed of at least 1/1000 second. Adjust depending on how much light you’ve got and if you’re still getting motion blur.
• You can also use a slower shutter speed if they’re coming toward you, just prefocus on where they’re gonna be, and lock it.
• Get close and get low—it makes even little jumps look like massive air
• If you’re usin’ a point-and-shoot (a shock-and-freeze proof model’s the way to go), it should have a sports mode to do most of the work for you. Fill flash will help you out as well on detail.
• To get fancy, you could try an action flash technique which’ll catch a skier against a color motion blur. The basics of it are to use a rear-curtain sync flash (which is useful for a lot of stuff anyway since it fires at the end of the exposure, so you should get familiar with it if you aren’t) with a slower shutter speed in a lower light situation. You’re probably gonna have to play with it a bit, but make sure you watch out for bright lights.

I might also add that you might want to use a waterproof digital camera case just in case you fall while taking pics.

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