Control the direction of your putt before you hit it and control distance by using this simple drill
Stradeling a string on the ground will help you see immediately if you stay centered throughout your swing or if you are swaying back or forward through the shot which leads to a faulty impact position
Start with a neutral grip making sure that your left hand is not turned over or under the shaft, this will prevent you from manipulation the clubface at the top of the backswing