When you take your stance, you need to be balanced at address. This means your left shoulder should be facing the target and your left foot should be right underneath your left shoulder.
To get the most out of your turn, do not grip your club too tightly. When you hold the club at address, it should be at a "5" on a scale of 1 to 10. Holding your club tighter than this will restrict your movement when your turn.
You want to ensure that you will have an effective power turn by having a good backswing. When you bring your club back, you should turn your hips all the way to the right before coming forward.
This is where the power turn comes in. To get the most out of your swing, turn your hips to the left after you have reached the apex of your backswing. Once you bring your hips through, they will generate sufficient power and allow you to get maximum clubhead speed at impact.
You must follow through completely or you will negate the effect of your power turn. Do not stop your swing until your club has reached shoulder level on your follow-through. At that point, you can look down the fairway and see where your ball has ended up.