For a right handed golfer one of the easiest ways to start the back swing, and one of the ways is to start with the left arm and left shoulder one piece back swing. You’re starting relatively slowly so you have a little bit more control over what you are doing. Now on the start of the back swing, the golf swing is what we call a bit of a kinetic sequence, so it starts with the hands, the arms, the shoulders and then on the down swing, it’s the opposite, so it’s kind of feet, the knees and the hips driving through.
Right Hand Golf Tip: Why you Should Start your Swing with the Left Arm and Shoulder (Video) - by Peter Finch