First... avoid putting from a static position.

Okay... what does that mean? Well just this. You want to get
some "movement" started before you begin the backstroke. Pro
golfer Bobby Schaeffer suggests you line up your shot... settle
in for the putt... then just before you begin the backstroke,
perform two gentle up-and-down "taps" with your putter head.
That's it. This avoids the kind of inaccuracies and putter head
"bobbles" that come from a static start.

Second... about your putting stroke. Remember to focus on
keeping the putter head low to the ground - this helps to keep
the putter on plane These two tips will do a couple things for
you. It'll suddenly give you greater consistency and accuracy
with your putts because you've avoided starting from a "static"
position... AND you'll never again "stub" your putts because the
"tap-tap" feeds your brain with a measurement of where the grass
is. Good stuff that'll instantly lower your score.