No matter what type of stroke you use on the greens, you'll sink more putts if the putterhead is square and accelerating through impact.
To achieve both conditions, try the following tip: On the follow-through of a normal putt, let the putter swing to a foot past the impact position and stop, making sure the face is square to the target. Only on the longest putts will you have to follow through more than a foot, so making an effort to reach that position will help you accelerate through the ball. Keeping the putterface square to that point is an indication that you kept it square throughout the stroke. If it points left or right, your ball probably went that way too.
Private Lessons 1999 Times Mirror Magazines, Inc., used under license by GolfServ Online, Inc. Instructional information provided by Golf Magazine.