Here is a simple drill that will help encourage an accelerating stroke when putting. Go ahead and setup about 5-10 feet away from the hole or target, place a headcover or range bucket about a foot behind your putter head. The headcover or range bucket will get in the way of your backswing. This will automatically force you to keep the backswing short without hitting the object and encourages the proper acceleration into the ball. Finally, when you feel confident from this range, move back to 20-30 feet (move your object back a few inches for each 5 feet in distance). This will help your speed control and is the key to eliminate 3-putts!
How many putts did you have during your last round?
30 or less should be the goal!