The putter's blade needs to be square to the path of the stroke through the hitting area.

You don't want to put a slice or hook spin on the ball because if you do, on its first contact with the ground, the ball will travel in the direction the spin wants.

The perfect takeaway should be online and square to the ball-target line. Otherwise, there's room to make errors.

If the putter is open on the way back, it must return to square at precisely the right time to propel the ball down the line. Alternatively, if you're square on the backswing, square at contact, and square on the follow-through, you don't have to rely on perfect timing to get the ball to stay online.

Square to square on an out-to-in or an in-to-out path will still put a spin on the ball. So you need a putting stroke that's square to square and online throughout. Only when you can achieve a square-to-square stroke online does the ball start where you expect it and continue where you wish it. The square to square is when the putter is one ball before and after impact.

 How to find out if your putter is open or closed at impact. 

Putting two balls simultaneously provides feedback on the putter's face angle at impact. The two balls must be positioned precisely perpendicular to the target line, or you can use special balls connected by an axis. Only if the balls are hit with a square putter face at precisely the same time will both balls leave the putter at the same speed and direction. If the outer ball is leading, the face at impact is closed. If the inner ball leads, the face is open at impact.

Examples of training aids

Practice putting with the Putting Gate; you will learn to square the face at impact and make more putts consistently. Hit your putting stroke with The Deuce 2-Ball Training Aid, and you get instant feedback for the perfect golf stroke. 

• It can be used with the SKLZ Deuce 2-Ball Trainer (included) or any golf ball.

• Gates are adjustable to fit any putter and increase the degree of difficulty

The True Path Putting Trainer was designed after years of studying the putting strokes of Tour Players, top PGA club professionals, and top amateurs. In the TaylorMade putting lab, data from thousands of strokes was analyzed to determine common faults and the best techniques of some of the best players in the world. Face angle and putter path are both important in successful putting. The best putters have a path no more than 2 degrees outside or inside the line.

The most common successful putting paths are

1. Straight back/straight through and
2. An arc from inside to square to inside.

Most scratch and Tour Players have an arced path identical to the one provided in the TR3 True Path.

• Consistency in putting the stroke path
• Instant putter face alignment feedback
• Improved muscle memory for proper putting stroke path
• Improved putting tempo
• Visual and audible feedback on putting path flaws