Correctly judging the speed of a putt is more important than correctly judging the line of a putt. This is why you should spend the majority of your practice time trying to improve your putting speed. If you correctly execute the speed of a putt but misjudge the line, you will most likely miss the hole by a few inches to possibly a few feet. If you misjudge the speed of a putt, your margin of error is considerably larger. A badly judged downhill putt can easily roll 20 to 30 feet past the hole. Here are some drills that you can practice that will improve your putting speed control.
Difficulty: Moderately Easy
Practice putts of varying length starting with long putts first. Stroke 10 to 20 putts that are approximately 40 feet in length on a level putting surface. Then repeat this same process for putts that are 20, 10 and then 5 feet in length. Repeat this same sequence for uphill and downhill putts of the same lengths.
Place impact tape on the face of your putter and then stroke a straight, 10-foot putt on a level putting surface. Look at the face of the putter to see where the ball made contact with the putter. Then look at the length that the putt traveled and make a note of the two results. Practice 20 more putts using the same drill, changing the impact tape as needed. Review your notes to determine your pattern of off-center putts and how the distance from center affects putting speed.
Place five balls in a line and then select a 10-foot putt that breaks approximately 3 feet right to left. First, visualize the line of the first putt and then stroke the ball. Follow this same process for each of the four remaining balls. This drill will improve your ability to judge the relationship between line, speed and break of a putt.
Practice putts 10 feet in length until the balls are consistently stopping no more than 6 inches short or long of the hole. Using your line of sight, lay a tee on the ground marking the length you believe your backswing will need to travel in order to execute a ten foot putt. Then stroke 20 10-foot putts focusing primarily on the length of your backswing. Repeat this same process for putts of varying length.
Repeat these same four practice drills on putting greens of varying speed. You will learn that speed control varies significantly on greens that are naturally faster or slower depending on type of grass, length of grass, moisture and so forth. Note that speed control of uphill and downhill putts will vary the most relative to changes in the speed of different greens.