Hitting with a flat left wrist is the great ball-striker's secret: Poor players usually think about the clubhead and the ball at impact, and how to use their hands to increase power or lift the ball. Good players think about their motion -- and keep their hands quiet.It's hard to resist the temptation to try to help the shot up, or to add a little more "juice" at impact. But by achieving the most important angle in golf -- the flat left wrist through impact -- you keep the bottom of your swing in a consistent place and strike the ball solidly. More important, you're letting the energy generated in the backswing multiply into the shot, which is much more powerful than any hand action.Here's how to use some simple school supplies to see, set and keep that angle.Tom Ness, one of America's 50 Greatest Teachers, is based at Alpharetta Athletic Club, Milton, Ga.