I determine the maximum break of a putt and then pick an aiming point either to the left or right of the hole. On big-breaking putts I pick an intermediate spot along the break—closer to the ball than the hole—and just roll the ball over the spot. It’s the same principle as in spot bowling. 

Bruce Edwards, my former caddie, thought that I putt better that way. He gave me the intermediate spot on the 45-foot putt I sank on my 16th hole of the first round of the 2003 U.S. Open, the putt that hesitated on the edge before toppling in. 

Most players underestimate the break and miss putts on the low side of the hole. Gravity pulls them down, away from the hole, and they never have a chance. 

When in doubt, play more break. And the faster the green, the more the break. 

On long breaking putts, the ball won’t break much at the start, when it’s hit hard. It will break more when it loses speed.