1) When you setup the unit turn, the racquet tip is straight up. There may be some layback in the wrist.
2) Optimal stance is neutral rather than open.
3) As you take the racquet back, you aim at the ball with the finger tips or palm of your oft-hand.
4) As you swing forward, pull from the buttcap to the ball.
5) In terms of muscles, you're swinging with mostly your triceps and upper pecs.
6) Finish over the shoulder.
Directory of Tennis Warehouse Clubs (courtesy of Mountain Ghost)