How to use the simple training aid loved by Tour pros

If you’ve ever stood around the practice green at a tour event, you’ve likely seen players using a thin string as they putt. It’s called a start-line string or an alignment string, and it’s one of the most effective — yet underrated — training aids for dialing in your putting. 

Recently, Ian Poulter shared a behind-the-scenes video explaining how he uses this Tour-trusted training aid to boost his alignment on the green — and how you can too.

How to use an alignment string

The string is stretched between two stakes and runs directly over your target line, giving you a visual guide to align your eyes and putter face. To set it up, Poulter says to put one stake behind the putt line and the other, down behind the hole. 

“Roughly where you think where the ball is going to move from,” he says. 

From here, he says to hit a few putts to see if your intended start line that you selected reflects what the ball is actually doing. 

“You want to see if your eyes picked up how much the ball is going to break,” Poulter says, “This is a really good test.”

You should be able to tell immediately if the line you selected is correct. If your start line is off, simply adjust the string by moving the stake behind the hole to account for any additional curve in the green you didn’t see at first.

Once you have your aim locked in, you can check your start line. All you have to do is watch your ball after you hit it. If your ball rolls directly under the string, you’ve started it on the correct line.

Not only will practicing with this tool improve your alignment, but it will even help you become a better green reader. You can also use the alignment string to check your eye position — a crucial aspect of the setup — and stroke length.

To check your eye position, Poulter says to set up to a ball with your putter — with the string over the midline of the golf ball. Grab a second ball and bring it directly under your dominant eye. Then drop it from this position. 

“You want that ball ideally to land straight on top of the ball that’s below,” he says, “That means that your eyeline is straight above the line.”

To check your stroke, Poulter says to place two tees down to mark the length of your stroke.

“You would like, in an ideal world, for the backstroke to be exactly the same distance as the follow through,” Poulter says, “That helps to give you a nice tempo back, slight acceleration onto the actual ball itself. And then as the putt finishes, it finishes the same distance on the way through, as the distance you’ve taken it back.”

The alignment string might be a simple tool, but as Ian Poulter shows, its impact on putting performance can be huge. Whether you’re working on aim, eye position, or stroke consistency, this underrated training aid gives you the fast feedback you need to putt like the pros.