Don't squeeze the life out of the club. To ensure you avoid this, extend your target arm. Hold the club at an angle in front of you with the heel pad of your left hand on top of the handle. This puts the club across the top joints of the fingers (where the fingers meet the hand).
The heel pad supports and traps the club, relieving you of the need to hold it in a death grip.
Some final words of wisdom:
One of the most common errors among golfers is a weak lead-hand grip (left hand for the right-handed golfer). This produces a shot that slices and lacks power. So later, we'll cover how to avoid slicing.
Left wrist and forearm strength are critical to golf success, so we'll discuss some good exercises elsewhere. But for now a simple daily routine is to hold the club straight out in front of you using the last three fingers of the left hand. From the wrists, move the club up and down 10-12 times. Three controlled sets without bending the arm will strengthen your muscles and get the proper motion into your muscle memory.
Practice daily, and try to build up to a consistent grip.
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