On every swing, your right side delivers the power while your left is there to keep things in order and in sequence. These are two very important—and different—roles that you should train independently to create a smooth, consistent overall motion. To work on your trail-side move, grab a mid-iron make right arm-only golf swings like I’m doing below. You don’t need to hit a ball for this drill, but you can if you’d like to.
Without feeling rushed or hurried, let your right arm and the club drop from the top. Feel as if both are moving toward your right hip. As the club continues to get closer to the ball, let your right arm release the lag you created on the backswing, unhinging your wrist and the club into impact.
Don’t excessively roll your forearm as you swing through impact. This will cause the face to close too much relative to the path. Instead, allow your right wrist to go from extension to flexion, as it does when you throw a baseball or shoot a basketball. This releases the clubhead, sending it around you and to the left but with the face remaining square to the path. That adds up to power and accuracy.