Inside-out: From an open stance. you'll swing back straighter and deliver the club from the inside.
The typical slicer takes the club back too far to the inside, runs out of room, and then has to lift the club to complete the backswing. From there, the downswing is steep, and the club cuts across the ball from out to in, producing a pull or a weak slice.
If that sounds familiar, here's a drill to help you start the club back straighter and shallow out your downswing. Set up in a dramatically open stance, with your feet aimed 30 or 40 degrees left of the target. Then swing back along your stance line. This will prevent you from pulling the club to the inside and will create a wider arc. You'll get into a lower, flatter position at the top (below).
On the downswing, the only way to swing toward the target is to feel as if you're pushing the club way out to the right. Another good feel is that your right shoulder stays low; most slicers get the right shoulder too high on the downswing.
These moves will feel awkward at first, because you're reversing the shape of your swing, so start at 70 percent speed. Work your way back to a square stance or stay open. Lee Trevino set up extremely open, and he was one of the best ball-strikers ever.
Jim McLean, a Golf Digest Teaching Professional, is based at Doral Golf Resort & Spa in Miami.