If you're the type to enjoy the bunny hill on a warm day, spend some time in the lodge, and create a social adventure out of your ski day, you may not need too much preparation. But, if you want to do all you can to help avoid injury at any level, you may want to get in shape before you hit the slopes. It's no secret that your legs do most the work while skiing or snowboarding. Working up endurance by jumping rope, or jumping side to side, and doing squats and lunges (properly of course - no knees past the toes) is important, but don't forget about stretching. That goes for your back and upper body as well. Your back does a lot of twisting while skiing or riding. Beyond that, you need to prepare for falls - where you can really twist it up. Being flexible and strong can help. You also want to make sure you have safe equipment that is fitted and tuned properly and that your winter wear fits properly, isn't too tight and isn't so loose that it gets in your way.