Many players have a problem with losing their grip on the club at the top of their backswing, forcing them to "regrip" the club as they start down. This is a common problem, even mentioned by Bobby Jones in his book, "Bobby Jones on Golf." You can easily prevent this problem can be easily, however, by taking a few simple precautions.
Check your club grips and make sure that they are in good shape and fit comfortably in your hands. If your grips are the wrong size for your hands or have become worn, they can cause you to lose your grip at the top.
Use a towel to make sure your grips are dry when playing in damp conditions. Wet grips make control difficult.
Use a golf glove if you need one. Sweat can make your grips as slick as rain.
Grip your club correctly. Ben Hogan spent a considerable amount of space describing a proper grip in his book, "Five Lessons." For a right-handed player, the left hand is the crucial hand. The butt end of the club should rest underneath the heel of the left hand. In fact, you can hold the club in position if the butt of the club is under the heel of your left hand and your left forefinger cradles the shaft. From this position, simply wrap your fingers around the club.
Use the correct grip pressure. Hogan noted that the last two or three fingers of the left hand – the pinky, ring and middle fingers – provided most of the pressure, and they didn't need to grip too tightly if the club was held properly. He warned – as Bobby Jones did in his book – that a too-tight grip was just as bad as a too-loose one. The traditional image of holding a bird in your grip, with just enough pressure to prevent its escape, is a good gauge to use for proper grip pressure.
Swing the club at a comfortable speed. If you swing your club too fast on the backswing, you'll struggle to keep the club under control at the top when you change direction and start the downswing.
Don't overswing or try to get extra wrist cock at the top. If your wrists are relaxed, they will cock as much as they can without extra help from you. But if you try to create extra wrist cock by manipulating your wrists or the club at the top, you'll put too much stress on your wrists and fingers and have trouble keeping a firm grip on the club.