You need to find a nice sturdy one that's not too steep for your first one. Other than that just get comfortable doing rails and down rails if you have any in your local. Basically just commit to it
Jump high and actually get on top of it, so much easier and looks better. Make sure you have enough speed and commit, everytime I've committed I've had small bails or landed, the time I didn't I got tangled up on the rail and completely ate it