After learning the proper fundamentals (posture, grip, aim and ball position), the best thing golfers can do to develop their games is to understand ball flight. By that I mean identifying shot shape, and then working back to see what caused it. Golfers often misunderstand -- they think a pull is a hook because both shots go left -- and as a result work on the wrong things.

The keys are identifying first where your ball starts and then which way it curves. Let's fix some common mis-hits: the slice, the pop-up and the hook.

Matt Killen, one of Golf Digest's Top-20 Teachers Under 40, is based at The Club at Olde Stone in Bowling Green, Ky. He works with Kenny Perry, J.B. Holmes and a number of other tour players.