"Gripping" your cue can be a very misleading term, because it implies a strong force and hold on your cue. However, clenching the cue like a baseball bat will tense up your forearm. Try comparing how steady you are able to keep your forearm when it is relaxed and when it is tensed up and how smoothly you can move your forearm. See the difference when you're tense? This will prevent you from having a smooth, true stroke. Nor should you hold the cue in your fingertips so lightly that you are unable to steadily guide the tip of your cue to the desired contact point on the ball. Rather, you should have a light but firmly supportive hold on your cue. Some players have only the thumb and forefinger grasping the cue. Only these two fingers are in contact with the cue at the end of the backswing, and all the fingers come to hold the cue at the end of the follow-through. Do not put your thumb on top of the cue, because this will lock up your wrist, and it's very important for your wrist to stay relaxed. One way to practice a looser hold if you have made the habit of clenching your cue is to hold a few pieces of chalk in your hand along with the cue and play a few racks like this, all the time having an easy, lightly firm hold with your thumb and forefinger...just enough to stay in control, trying to avoid pressing the chalk into the cue. You'll definitely notice the difference when the chalk is gone.
At all times, your cue should feel well balanced in your hand. For normal shots, your hand should be in the center of the wrap (assuming your cue length is appropriate for your armspan). For shots that require more "touch" and accuracy, try moving your hand forward on the wrap, shortening the length between your bridge hand and the ferrule. For shots that require more power, try moving your hand back on the wrap, lengthening the distance between your bridge hand and the ferrule. Always remember to stay down and follow through on your shots.
