7!
I used to have this very same issue and have worked on it a lot. If you are a visual person I highly recommend going on youtube and watching some pros. A good rule of thumb though is too make sure that your back swing is slower than your forward and the transition is smooth or only has a slight pause for a few reasons. 1. Its easy to pull the cue straight back 2. Your follow through isn't fighting the momentum of your backswing. 3. its near impossible to decelerate through the ball which will mean punching it, miscueing and poor gas mileage! 4. Your cueball control and accuracy willl increase dramatically. It is much easier to "feel" the speed of the shot this way.
Imagine a slingshot, The hammer on a double action revolver, a golf swing (that isnt too crazy). The speed back is almost always slower than forward. Hope this helps!
