Students come out all the time and want to work on their ball striking. After analyzing their statistics we learn they hit a fair number of greens but have way too many three putts! The following tip and practice technique will help you reduce your number of putts per round and lower your scores.
There are two primary aspects of putting: line and speed.
The line portion is taken care of once we line up the ball and putter during address. Most players spend way too much time worrying about and thinking over the putt about the line and not near enough time thinking about and visualizing speed. Just as if you picked up a ball, looked at me and tossed it to me, you should use your eyes to tell you how hard to hit your putts. Take practice strokes while looking at the hole to allow your eyes to tell your brain how hard you need to stroke the putt.
This is a great drill I learned from Hank Johnson. Go to the practice green and work just on speed. Drop 3 golf balls in the middle of the green and roll putts at the fringe. The object is to get each ball closer to the fringe than the previous ball without touching the fringe. Spending time focusing on just speed without any worry of line will help you learn to develop more feel and better control over your lag putts.