Sloppy head action leads to fat shots. Not only should you keep your head in the same place during the swing, but consciously avoid head motion that's downward or to your right. Many top golfers' heads do move a little downward and to the right in response to the targetward thrust of the lower body. But if the motion becomes accentuated, they--and you--will surely catch the ground before the ball. Fat and thin shots are caused by the same problem: The club bottoms out before the ball.
