I was taught early on the connection between an athletic posture and a consistent golf swing. That means bending from the waist, arms hanging naturally, slight knee flex and chin away from my chest. Many amateurs bury the chin in the chest during setup, which restricts the shoulder turn and weight transfer.
If you have that problem, picturing some familiar athletes might help. Visualize a skill-position football player -- quarterback, running back or receiver. They always keep the head up, ready to make a play. Similarly, a hurdler would have a tough time clearing a hurdle if the chin were tucked between the shoulders.
Tiger Woods writes instruction articles only for Golf Digest.