After you've mastered putting balls in-between each set of strings, from the closest to the farthest, start mixing it up. Putt to the last string, then to the first, then to the third, and so on.
If the ball stops between your target strings, the longest "second putt" you will encounter will be 18 inches (imagining the hole located midway between the strings). Remember to use your eyes - look and react.
It is uncanny how good your direction control is when doing this drill, and please take your mind off the line. Line-bound putters tend to have poor distance control. Loren Roberts told me once that he feels he can make a putt on any green if he hits it the right speed. He said that when he putts, all he thinks about is the speed he will roll the ball.
Try this lag putting drill next time you're on a practice green and your distance control is sure to improve.
