Regardless of skill level putting accounts for approximately 43 percent of your total strokes taking into account your good putting days and the ones where you’re ready to snap your flatstick over your knee. Lower this percentage and your scores will go down. Allocate at least one-third of your practice time to becoming the best putter you can be.
At my schools we preach the importance of the 20-foot putting stroke since 20 feet is the most common putt length in golf. So any student of mine facing a 15-foot putt on the course will preview some small adjustment to that 20-foot reference stroke during their pre-putt routine factoring in the other conditions of the putt that are computed as you read the green such as slope break grain wind etc.
Once set step in and repeat the preview in every detail. More importantly feel good about it. A preview should fill you with confidence. I have no doubt that if you give your putting previews your best effort everything about your putting will improve from your sense of feel and touch to your ability to roll it in from anywhere on the green.