2. The other error in the backswing is a very vertical lifting of the body and arms. If your arms look as though they swing straight up away from the ball and that your body lifts out of your address position, then you need more rotation in your golf swing.
Check your grip and address position carefully. Then make practice swings holding the club out in front of you about waist high off the ground. Look at the video and then repeat what I am doing in a mirror.
Keep your lower body braced and roll your arms and chest aggressively in a circle. This is the feeling that you will need to correct your backswing.
Exercise to Eliminate Left Divots
If your clubface swings across the ball on an outside to inside path then you will have to have an open face at impact to spin the ball back to the target. Slice spin is very weak and hard to control.
When you are hitting balls using the exercise you should try the following thoughts.
I check my grip and set up to the ball with a good balanced address position. I concentrate on keeping my body still as my arms work up my chest. You can see that my hinge is full to 90 degree by the time my left arm is parallel to the ground.
As my arms start down to the ball you can see how my weight stays held on my right leg and how my chest waits for the arms to swing down. This allows me to swing on a more inside to out path and I can fully release my arms without any fear of a pull hook. My ball starts slightly right of the target and gently turns right to left in the air and falls down on the flag.
Go to work!