Don't ever think of it as failing. It's all a learning experiance.
Are you getting the jumps filmed? If so review it with your instructor and see what you can change.
Practice the jump on the ground over over and over!
When you are going up in plane, close your eyes and visualise the jump.
Just before you exit, take a few deep breaths to calm down.
When doing the jump, relax and smile, have fun! Because being tense doesnt make fly very well!
FYI This is what I did during my AFF and what the instructors told me!Quote