First, position yourself at the center of the trampoline. Get a feel for the trampoline and get a rythm going before starting. Begin by bouncing at a controlled, consistant height. At the climax of each bounce, bring one leg high into the air as though you are kicking. Bring the leg back down before landing. Repeat, alternating legs each bounce. Repeat a series of repetitions that you are comfortable with, take a break, and repeat.