For rails fully 90 on to them, have a wide stance, good speed, look down the rail, dont get up on your edges, and stomp that thing.
For jumps find a more private jump and just pracice some gay looking things until you feel comfident on the big stuff.
EG: for 3's do a 270 adn butter out to build your confidence up or for 1's which are real easy practice on the flat