Mountains of books, chapters, articles, poems, sketches hae centred on the subject. Styles and fashions in putters and putting are an industry in themselves. There is no one secret. A good putter can hole putts with a garden hoe. A bad putter can avoid contact with the hole from 18 inches with  £800 worth of putter. Hopefully something someone contributes here will click on a bulb and offer you at least temporary relief from the worst of the horrors.

Best tip ever!  Every Putt is a Straight Putt. Once you have  computed in line and pace all you have to do is select your imaginary landing point and hit a straight putt to it. Don't try and influence where the ball is going by changing anything. Just take your putter back, follow through square and listen for the CLUNK as it takes the borrow off your landing point and drops.

Let's start with the fundamentals as seen by Harold Swash, the world renowned putting guru.

 Fundamental No 1 The blade of the putter needs to be square to the target at both the address and strike position.

Fundamental No 2 The blade of the putter needs to be square to the path through the hitting area.

Fundamental No 3 The putter blade needs to have a slight up stroke through the hitting area.

Fundamental No 4 The putter blade needs to have a smooth acceleration through the hitting area.

TRUE ROLL - THE GUIDING PRINCIPLE The guiding principle that governs Harold's coaching and blends together his four fundamentals is the need to develop a true roll on the ball. The quicker a ball starts to roll after impact the better chance it has of staying on its intended line with its intended pace. It is the underlying principle that directs Harold's coaching.

Harold's views on the mechanics of the stroke such as the stance, posture, stroke plane and the grip just to name just a few are all geared to helping you achieve this basic principle.

(courtesy of http://www.haroldswashputting.co.uk)

from EGU Coach Alasdair Barr

Best tip to stop the yips and three putting: To eradicate the 'heebie geebies' on the greens a three drill routine should help to ease the problem.
1.    To encourage a free swing of the putterhead eliminate the two problems - the ball and the hole. Hit a few putts on the green without using the hole and do this with the eyes closed. This will encourage a smoother stroke and return the "feel" sensation as there is nothing visual.  Hold the putter as lightly as possible to remove tension from the forearms.
2.    Introduce the hole and make the stroke looking at the hole. This focuses the brain on "what you want" and not "how am I going to do it."
3.    Now return to the normal set up visualising the ball falling into the hole as in exercise 2, and do not concentrate on the mechanics of the stroke.