A little something I used to do when I started skiing park, kind of a douche move but whatever : Before you go riding with a bunch of friends, tell them last time you went skiing you landed, lets say, a frontflip. Now we all know that when we are off the hill, everything seems way less scarier than when we are in front of the feature waiting to drop in. So it shouldn't be a problem being confident that next time you go with your friends, your are REALLY going to do a frontflip, only difference is this time, you won't be able to pussy out since you told everyone you already landed it (lets say atleast once).
A less cocky variation would be to just tell all your friends at school that next weekend, you are fucking doing it, and if not, you have to give everyone you told a small amount of money.