Admit it, you love watching the ball roll into the hole. Unfortunately, many golfers miss putts they should make because they're anxious. If you take a peek before you've completed your stroke, there's a good chance you're going to roll the ball off line. When you turn prematurely to look, your weight shifts onto your back foot, and your upper body opens (above, left). This causes the path of your stroke to move inside your target line, and all you get to do is watch a miss.
Here's a drill I use with my students. It helps keep your body steady until the ball is long gone. Next time you're on the practice green, set your back foot up on its toes, placing the majority of your body weight on your front foot (above, right). Now hit a putt. Even if you peek before the stroke is complete, your body won't open up and alter the path because you can't shift your weight onto your back foot.
Now when you miss a putt, it's the green's fault.