If you're making controlled, balanced swings but still find yourself hitting a random assortment of hooks and slices, your backswing may be the problem. Chances are good that you're taking the club back off plane and then not making the necessary compensations on the way down to the ball. The truth, however, is that you don't need to make compensations — you just need to fix your backswing. Here's how to do it.
First, lay your driver across your shoulders with the grip end to your left. Now take your stance, making your regular backswing and stop at the top. Where is the butt end of the club pointing? You may have read that it should point directly at the ball on the ground, but that creates an overly steep, slice-producing swing. On the other hand, if the butt end is pointed way beyond the ball, your swing plane is likely to be overly shallow and prone to producing hooks.
The correct way to perform this drill is to turn your shoulders and maintain your posture so that the shaft points at a spot a foot or so on the other side of the ball. That's a perfect on-plan position. Combine a nice, smooth backswing with this exact shoulder turn, and you'll be in perfect position at the top.