A few advanced safety tips:
If you ski in steep terrain, practice self-arrest: Self Arrest Techniques
If you ski in the backcountry, become an expert with your transceiver, probe and shovel
Spot your landing before launching air
Heed avalanche warnings
In the backcountry:
Keep away from avalanche routes like gullies
Steer clear of depressions in the snow for these can be crevasses
Ski down the fall line rather than cutting back and forth across the slope...
ALWAYS ski with at least one knowledgeable partner. Two are even better.