Replying to New to park skiing

Hey, I just started park skiing last year I learned to do 180s and it some "ride on" rails, This year I have been trying to progress I have learned how to hit ride on rails better and I can come off switch and I want to learn 270 off or on and 360s. The main problem I have is rails that have a step up or jump up and I'm always very intimidated by them because I feel like I can't get that much height. Any recommendations on to hit these easier and to hit rails easier in general because I seem to always slip off especially on kinks?