The diagram below illustrates what happens during a stroke. Your elbow should not move. Only your fore arm from elbow down moves during the stroke.

As the hand moves the cue stick toward the cue ball with a level cue the tip moves through the cue ball level. As the hand begins to rise the arc of the tip goes down toward the table. If your elbow does not fall and your body does not move forward the tip will hit the table somewhere around 6" from the tip side of the cue ball at rest. This is the extent of the follow through on a normal stroke.

No matter where you hit the cue ball the arc of the stroke should be the same. If you shorten your stroke you can avoid contacting the table. If you cue very high on the cue ball the tip may not contact the table but the arc should be the same. If you cue low on the cue ball you will contact the table early.

The cue tip should hit table at this point.