You've probably tried everything, but your golf handicap is still climbing. You have bought more putters than socks, but you still you miss several makeable putts. Perhaps it's time you tried a belly putter. A number of players on the professional tours use them with great success.
You won't have to learn a new grip just because you have converted to a belly putter. If you use a traditional overlapping grip with your conventional putter, there's no reason to change. Use whatever style of grip that is comfortable, but make sure you do not put a “stranglehold” on your belly putter. Think of how you would hold a small squirrel. You would hold it tightly enough so it would not get away, but softly enough so you would not hurt it.
Many golfers try to compensate for their shortcomings on the green by contorting the way they stand when they address the ball. If you convert to a belly putter, your stance is an important element of success. A belly putter will only be effective if you take the proper stance because you must place the butt end of the putter somewhere above your belt on the center of your torso. Work at spreading your feet about as wide as your shoulders and line them up in a direct line with the hole.
Take the belly putter back, then bring it forward without your wrists breaking. Many golfers fail to keep their wrists from breaking when using a conventional putter, so they resort to putting cross-handed. Try the following technique to make sure you are hitting the ball in the right direction: 1) pick a flat part of the green and run string from your ball to about 20 feet away; 2) hit a few balls down the string and note whether they move left or right. If you are right-handed and the balls tend to go to the right of the target, then you are opening the club face. Conversely, if the balls are going to the left, you are probably shutting the face before impact. Work at keeping the club square throughout the swing, starting with an easy rotation of your shoulders.