The biggest issues are physical fitness and skill level. Make sure you are in good shape by doing lots of cardio, leg and core workouts. As far as skill goes, take baby steps to get better. If you try things way out of your skill level it makes it easy to get in an accident. Many ski injuries are caused from simply overestimating your own abilities. I even got injured the other day from overestimating my physical strength, and I definitely learned a valuable lesson!

This isn't to say you shouldn't do the more difficult terrain, but rather make sure you are prepared to handle it.