Even though gripping styles vary greatly, one thing remains constant. It is absolutely necessary that your hands are kept close together when you grip your putter. Gripping the putter with your hands too far from each other will throw off the accuracy of your stroke. Always grip your golf with your hands so close together that the thumb of your upper hand is covered by your lower hand.
When you do this Right Hand Only drill do be conscious of the toe of the putter in the follow through. Should the toe turn away from the cup this means you are turning your hand. You know you are doing it right when the face of the putter is square to the cup.
Have you remembered the stance? Feet firm, hips firm, head still, looking down at the ball. The only movement is the ridged arm plus the putter being moved by the shoulders enough to draw the putter back to pendulum through the ball and finish ahead of where the ball was.
Some may be wary of an online stockist for golf shirts or golf gloves because fit is everything, especially with the gloves. However, a good online retailer will make returns easy and painless. Once you have found an online golf shop that can fit you right and gives you a great price, you know you can stick with that gentleman for future purchases.
Moving on, the trainer should assess the golfer's ability to rotate the torso. The golfer must be able to rotate the torso to some extent without turning the hips or shoulders. An inability to rotate the torso might result in a compensation elsewhere, such as an over rotation of the hips in the back swing.
Crafting a perfect swing requires more mechanics and thought processes than almost any other sporting movement. You need to think about your grip, swing plane, torso movement, arm and leg positions, back alignment and plenty of other issues.
Back swing - Do not underestimate the importance of your backswing. How many times have you taken your club back, not felt comfortable and certain that you are going to fluff the shot... and then you do just that. Take your club back using your body, not your arms, and bring it back down on the same path.