Know your slope-schussing ability!
Do not overestimate your ability on the slopes. Do not forget that you may have aged a few more years since your last ski trip.
Nothing wrecks a trip to the mountains more than getting a metal rod inserted into your tibia. : )
Note the t-shirt pictured below.... "Catskinner" is one of Red River's more deadly slopes. The t-shirt says "donate blood, ski Catskinner". It's meant to be funny, but the message is serious.