To panic in the air is a major obstacle. I'd suggest finding jumps that range in height, distance, speed, slope, etc. and work on starting small (shorter, slower, flatter) and working your way up (longer, faster, steeper).
The attack position is what you need to attain, especially in developing good technique--elbows up and looking ahead of your course. Let the bike rock under you while keeping your head stable, like you're holding a coffee cup on it. You don't neccessarily have to be at peak hp when hitting the lip, but should be on the gas and in the attack position. Letting off the gas after you're in the air will naturally let the front end level without having to tap the back brake. Letting off the gas before takeoff will create a nosedive. If you keep the throttle pinned, torque of the rear wheel will want to get your front end up more. Maybe practice preloading on tabletops and see if that helps. Hope this was a touch helpful... have fun!