Start low and work your way up. I would try to avoid stepping as sometimes it becomes a crutch for people that's harder to get rid of than just learning. If you can slide down rails it's not bad.
Basically when you set a low down rail up, a lot of times the point where you land is actually the same height or only slightly higher than the takeoff. IF you carry some speed you'll travel even farther down. The shorter the length of the rail the better. IF you have something like 8' that's perfect. Then when you hit it you're kind of just tapping the end. Getting comfortable landing on it from the side, if you get off balance you're sliding for such a short time a lot of times you'll land before you'll fall.
If it's super low you won't have to pop much and can focus on getting yourself fully committed to getting sideways and being balance so you don't slip out.
Granted I suck at skiing now and can't can only hit mellow, low down stuff and flat stuff right now.
But I think that's still semi valid advice.