Three, Six, Nine
Why this drill
Three putts at three distances, and the game only ends when all nine drop in sequence. Three-six-nine is the short-putt gauntlet that builds the one thing scorecards notice: certainty from the distances you face on every single green.
Setup
One ball, one hole with a reasonably straight line, and three tees marking three, six, and nine feet on the same line.
The drill
Hole from three feet, then six, then nine — full routine on each. Any miss restarts the whole sequence at three. Complete the ladder three times to finish. The nine-footer is the examiner: you'll face it repeatedly with a restart on the line, which is precisely the putt golf keeps giving you on real greens. Log how many attempts three clean ladders took; watch the number fall across the season.
One thought to take with you
The routine is the same at nine feet as at three — only the doubt is different. Leave it out.