gyms are cool n all, but really its so much better with ur friends in their backyard. its a sick sesh with ur friends, and at the gym sometimes they get angry when u flip or whatever, depends on the chillness of the staff.
im pissed my parents landscaped our backyard. and they took out the "eye sore" that i call my trampoline. now i spend my time working on the b yard not tramping, it sucks.
and safety is key, if u dont feel comfortable get a spotter or dont do it.