Your Snow Card is your access to the mountain. Keep it on you at all times so you have access to the lifts. You can keep it in a pocket and don't have to take it out for the gate reader to scan it. It's a great idea not to keep it in your wallet, or with a phone or other cards, as the reader on the gate may not be able to scan it.
If you have a Snow Card from last season, you don't need to get a new one - it can be reloaded with this year's pass.