Dodge Traffic and Collisions: To go right through a collision or on coming traffic simply do a turbo boost (A twice). Then you can do a trick off the car.

360: To do a 360, when you are at the top of the ramp push left or right.
Flip: To do a flip just pop a wheelie on a jump (press Gas twice). If this doesn't work, work on your timing.
Wheelie: To pull a wheelie simply press the Gas button twice while on a straight road. This will give you a small boost as well!
Sideways Wheelie: To do a sideways wheelie, while taking a turn, press the gas button twice. This helps you to take turns easier.
Barrel Roll: To do a barrel roll, first do a sideways flip by pressing the gas button twice while turning, now move the joystick the opposite way of the turn and you'll do a barrel roll.
Flip Roll - To do the flip roll you need to execute a normal flip during a jump, then press B,B,A,B,C-Up to roll in mid-air. You'll earn 20 points each time you do this.