The slice almost always starts with the body position and how you’re getting lined up to the target.  To correct a slice, one of the first things you should do is pay close attention to your initial set up to make sure that all your body parts are parallel to the target line.

If you’re front foot, for example, is opening up before you even swing, chances are your hips are going to follow causing your swing to go from the outside in and strike the ball in a manner that produces that nasty sideways spin that creates the slicing action.