There are greens that are so fast, all you need to do is tap the ball on a downhill lie to get it to the hole. I'm not joking when I say that at Augusta National, I'll practice hitting a putt with the speed to move it only one inch if the green were flat like the photo (below) indicates. It's a stroke that requires real touch, so I suggest you practice it if you're about to play on very fast greens.
The greatest putters of all time, guys like Ben Crenshaw, Jack Nicklaus and Jackie Burke, all said distance control was paramount. In addition to those one-inchers, find an area where you can alternate hitting 30-footers from well above and below the hole. Keep trying these putts until you feel just how much effort—and more important how little—you need to get the ball to stop by the hole if it doesn't go in. Try to keep your grip pressure constant as you do this. If you know how softly you have to hit a slick, downhill putt, you'll avoid one of golf's most embarrassing situations: rolling the ball off the green.
DOUBLE THE BREAK
If you're faced with the tough combination of a downhill putt that will slide left or right, remember that the break is accentuated by the slow speed you have to hit the putt. In other words, the ball will break a lot more than you might think.