Jeremy Dean is usually the man to talk to

Your feet, your back foot especially, are probably going to move around a fair bit. I'd recommend not worrying about it too much. Try to be front on and your feet will follow.

Im looking at your right hand. Open it up will open up your shoulder too. Think of it as serving a pizza on a plate to someone behind you.

Like graham said: At the moment you are using a side to side movemen to generate speed. You're hardly using the walls. Try going up and down the walls to generate speed instead.