Geez guys, you are missing the easy stuff.
For practice (you can initially do this against the fence):
1) put the inside of your arm against your ear
2) put the head of the racket down your back.
3) swing from there
you can do this first practice swinging with the racket edge hitting the fence
then, after a few times swing from the initial position with the forearm and wrist turning during the motion so that the stringbed would hit the fence/ball.
This should give you a good idea of the "backscratch" position.
Think of it as a whip or a catapult with a lot of hinge points.
Your motion is more of a shove, with the elbow never getting in postion to lead the forearm/wrist/racket.