What Are the Two Most Important Things in a Golf Swing?
This is the start of your swing and if you start off correctly, the chances are much better that you will be able to put a good swing on the ball. In order to have a dependable takeaway, you need to address the ball. For a right-handed golfer, you must have your left shoulder facing the target and your left foot needs to be directly under the ball. You should have your knees flexed and you should play the ball midway between your front and back feet. From this position you start your takeaway by rotating your hips to the right. Your hands, arms and shoulders will follow, but your first move has to be the rotation of your hips to the right in order to get your club into the proper position.
Moment of Impact
Lead to the ball with your hips. After you have rotated your hips all the way to the right on the takeaway, you have to rotate your hips all the way back to the left on the downswing. At the moment of impact, your hips should have just cleared the hitting zone as you lead into the ball with your left side and specifically your left arm. At the moment of impact, your left arm should be straight and your left wrist should be firm.
Putting it Together
The reality of the game of golf is that no one move is made to turn your swing into a work of art that produces nothing but effective shots. In reality, it is the golf swing as a whole that must be effective. You must have a great takeaway and be in the correct position at the moment of impact. Doing this consistently requires going to the driving range and practicing your swing on a consistent basis. Practice a smooth, strong and effective swing and don't try to bomb the ball all over the range.