yea. get comfortable on a trampoline. its the closest feeling without goin full on ramp. just get comfortable in the air, and how you actually set tricks. as for diving boards, they are fun, but i think since the force of the boards springback is forward, its really different to set rearward corks and backflips. they are easy to do bios and misty type shit, but i usually have to do corks and flips switch on um.
as for on snow, powder, OR, find a really well built and planned jump with a nice landing that matches the trajectory of the jump. that way, if you do land off axis, there wont be much of an impact.