1. Putt to the Fringe: with putter in hand, grab five golf balls and head to a flat spot on the green. Place a tee into the ground at the spot and drop the balls next to the tee. Turning to face the outskirts of the green, putt a ball towards the fringe of the green with a goal of getting the ball as close to the fringe as possible without going onto the second cut. Turn slightly and putt a second ball in the same manner, so that the objective is the same (the ball just reaching the fringe), but aim so as to putt the ball three to four yards the right of the first ball. Repeat the process turning each time to putt to a slightly different spot until you have putted all five balls. Ideally, you can find a flat spot that gives you five putts of different length.
2. Putt to the Tee: Once you have putted the five balls to the edges of the green, walk out and putt each ball back, this time making the tee you placed in the green your specific target. If in part one a ball or two goes slightly onto the fringe, I putt them from the fringe back. I like getting a feel for putting from the fringe as well as from the putting surface.
3. Putt to the Fringe and Back to the Tee, Part Two: I like doing the drill a second time on a sloped area of the green. Picking the right spot with an appropriate slope should give you at least one downhill, one uphill, and three slightly side-hill putts. By putting first to the fringe, then putting back to the tee, the three side-hill putts will give you some left-to-right breakers and right-to-left breakers in addition to those going straight uphill and downhill. Given the challenges associated with the sloped section, it makes sense to start a little closer to the fringe than you did when on flat ground.
4. Make Five: The last drill is designed to gain confidence and begin hearing that most pleasant sound, that of the ball falling to the bottom of the cup. Start four to six feet from the hole and make it your objective to make five straight putts. For this drill select a flat putt and use a distance that makes sense for you. The goal is to gain confidence as you warm up so if a four-footer is more appropriate for you to be able to make five straight, then practice that length.
5. Make Five, Part Two: Finish with the same drill but select a hole on a slope. Again using a very short distance (4-6 feet), make five straight putts, first making five that are up the hill then another five that are downhill. For pre-round warm-up purposes, I select putts that have very little break--no side-hill lies.
Remember, it's "drive for show" and "putt for dough," so don't skip the putting green during your warm-up routine.
Most importantly, warm up with a purpose. Don't bang the ball around the putting surface--instead, use these five drills to give you a quick feel of the green and get you 30 to 35 warm-up putts in a very short amount of time. Taken collectively, they will get you warmed-up, give you a good feel for how fast the ball is rolling and get you into the mindset that the ball will fall in the cup as long as you make a good stroke.