When you take off, turn your head in the opposite direction that you will be spinning. Once you get to the lip of the jump, you turn /whip your head in the other direction while popping to give you a solid rotation in the air, which you continue depending on the degree rotation you want.
When you are landing, it seems like you are pressuring your edges too much. Instead try to focus on absorbing the impact with your knees, and keeping the bases flat, which should help you to have a solid landuing and maintain speed. Also one reason you are loosing speed could be if the jump has a steep take off and a relatively flat landing. If you are coming down a lot more than you are moving forward, you will lose speed regardless of whether you are switch or forward.
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You Dropped Your Pocket!
Mont Tremblant '04