Instructions
Line your skateboarder up with the ramp from which you want to perform the double flip.
Skate towards the ramp and pick up speed by using using the left and right foot push buttons. These are the "X" and "A" buttons on the Xbox360.
Hold the left and right trigger buttons as soon as your skater launches off the ramp in order to grab the board.
Press and hold "UP" or "DOWN" on the left analogue to start the forward or backward rotations needed to do a double flip. Let go of the trigger buttons before touching the ground for a smooth landing.