The cue grip is the next important step in the formation of a good technique, the grip has to be firm but not too firm.
The cue is held lightly by all the fingers, with the thumb hanging loose.
Insure that the wrist is hanging down in a straight line from the elbow.
Like in Diagram 3.1 & 3.2
But in Diagram 3.3 The wrist is badly turned into the body.
Also insure that there is a full grip before you start your cue action.
Deliver the cue in the same way on every shot and make sure there are no movements in your wrist, other than the backward or forward motion on the line of the stroke
Common Faults
Griping the cue too tightly
Wrist cocked to the side
Not griping the butt with all the fingers
Wrist not hanging straight down
Thumb on the butt