To hole more putts, you must first have a good set up. You want your eyes to be positioned over the golf ball in your putting set up.
To practice a good set up and alignment you can use an old CD. With a Sharpie marker and a ruler, draw two lines perpendicular to each other on the shinny side of the CD. Place the CD shinny side up on the putting green and place your ball in the hole of the CD.
When you address the ball you want to see the reflection of your eyes on the CD. The lines you drew on the CD serve as an alignment aid.
Practice putting balls from the center of the CD. While doing so try to keep your head still during your stroke. If your head moves you will obviously loose site of your reflection on the CD.