I used to do backflips, but I'm damn near 40 now. Conditions have to be right (pow out west, perfect jump). I went to "Camp of Champions" when I was 18 and really started to get them down well, but you know how things go away if you don't practice. I always wanted to do two things: a big mute backflip (JP Auclair-style) and a Lincoln Loop off a cliff. Never did either one of those.
If you want to try it, look for a mountain with one of those big airbags and just pay for a couple of hours.
PSIA used to do a summer event (open to anyone) where they let you go off the water ramps in Lake Placid (and gave you some trampoline time and instruction), but it looks like that has been moved to an airbag, too:
https://www.psia-e.org/jump/