Bend forward and let your arms hang. This is how your left arm should be at impact. Your left hand grips where it naturally hangs so that momentum squares the face at impact.
Fewer than 2 or 3 people I have worked with have had a correct grip. A correct grip is one that fits you and your body. Everything in golf is done with your hands so having a correct grip is critical.
Now that we know where Impact Position is, let's train our swing from here. This will give you a strong sense of how to get to the ball.
For some reason, people think that they must turn their bodies in order to hit the ball. This body motion disrupts the spine angle and throws you off completely. Here's what your body wants.