When you are putting, pace is all-important. If you can't hit your putts at the right pace it doesn't matter how well you read the green or control the face through impact, you will never hole your share.
Before you head out in a competition, hit some long putts to no specific target. The idea is to get your balls to finish in a very tight dispersion. Once you've hit five balls into one area, choose another spot on the practice green to aim at and do the same. Then do it again. As you hit more putts your natural feel for the pace of the greens will improve. Then when you head out onto the course, you'll have a much better chance of hitting every putt at the perfect pace.
Selecting the right putter for your individual stroke is essential. If you are using the wrong type, you'll be giving away important shots. For some impartial advice on what to do, please go and see your local Foremost Golf professional.