You've heard the old tip for taking the club back: "Get your left shoulder under your chin." The problem is, you need to do more than that to achieve a powerful body coil at the top. You have to feel your upper body turning as you keep your arms extended but not rigid. To do this, forget about the left shoulder and focus on turning your right shoulder behind you. Feel it moving up and behind your head (above). This will increase your rotation and set the club better at the top, putting you in position to swing down with power.