Easy way to do a backflip on atrampoline
-Have someone hold one of your feet -Tell them GO when your ready -When your near to being in the air lean back a little bit -When all the way in the air lean all the way back holding your legs like your doing a cannon ball into a pool -Once you see your lined up to land,let your legs go
If done correctly,you should be able to pull it off
its basically the same as doin a frontflip. bounce real high, then when your ready..count 1,2,3 in your head then thrust your hips up and towards your head, then grab you knees and pull your as you go round, and you legs, that will give you the speed to pull it off. also therr might be some tutorials on youtube about flips. just be careful.
Just do it. lol jk...just throw you your legs in the motion and keep your upper body in place and DON"T jump back. Jump straight up and then do the flip.