For some putting is the hardest part of the game but for me it is the most gentle part. Of course technique is key here, but so is a good mental view-point. Often I will visualise the putt in my mind, seeking the line in my mind's-eye.
The set-up I use is 2 practice warm-up swings getting the feel for how the ball will travel from the putter. This helps me ascertain distance. Next is a good-read looking at how the slopes will effect the ball direction, left, right or up or down.
I keep an eye out for any impediment that will slow the ball, be it a leaf, piece of dirt or a small stone for example. Then of course remove the obstacle!
Next I breathe deep to calm myself and then prepare the shot in my mind again.
The success will come from firstly getting GIR and then ALWAYS 2 putting, never 3 putt :)
There is always the chance that your first putt will sink..