There's a reason more Golf Digest instruction attention has been devoted to the slice than any other subject throughout our history.
A lot of people do it, and it can be a hard problem to fix.
A lot of advice starts with changing the way you swing the club or the amount, direction and timing of your lower body movement. That advice can be fine, but many players are looking for a simple, single cue to get going on the right track.
Top Maryland teacher Bernie Najar has one of those cues: Your left arm. "When a slicer starts the downswing, the left arm moves excessively outward and away from the torso," says Najar, who is based at Caves Valley Golf Club in Owings Mills. "This mistake sends the club into the ball in an open position relative to the swing path."
To fix it, make some slow practice swings where you start the downswing with the feel of your left arm pressing against the side of your torso. "Groove this feeling and your left arm will stay to the inside on the downswing, and your slice will disappear."