In every aspect of your golf swing it is vital for the body to rotate forward toward the target rather than back and away.

To encourage better forward rotation move into your set up  set up position lift your heel of back foot so that only the toe of you shoe is lightly touching the ground. With the same leg, turn your knee so that the knee cap is pointing more towards the target.  You should now be set up almost in your finish position with your lower body.  Swing normally.  During the swing the heel of your back foot should not touch the ground at any point, especially in the finish position.  This will help create the sensation of the weight staying in the more centred in the backswing and allow you to rotate forward without thinking too much as you are already half way there.

Hit 5-7 shots in this set up and then test your rotation forward and balance by hitting a shot in your standard set up.  You are trying to recreate the awareness of rotating forward and keeping your weight more centred and eliminating any back and away weight shift.