You have to remove all doubt of falling from your mind, you only need balls if you're going to huck carcass and hurt yourself.
Instead just focus on the vision of what that trick will feel like. If you feel like you know what to do just focus on that feeling. Do this and not just throw yourself blindly off the jump.
You may not get it the first time but you will most likely get it to your feet and just scrub out a little bit.
Lastly, I have found over the years that there is a lot less physical effort required for most (simpler) tricks than you would think, ie: you do not need to wind up and put every amount of force into a five off a 20 ft jump.
For the things I consider "big"... I like to have some friends with me. Not to show off, just is nice to have some people around to pump you up. Right before I drop I visualize how exactly I will carve of the lip and set the trick. And right when I start to drop I like to take 2 deep breaths.