Don't leave putts short of the hole.
Par is established based on the assumption a player will hit from the tee, make an approach shot from the fairway (2 approach shots on par 5's), and make 2 putts on the green. On most golf courses, 1/2 of par is for putts. 18 holes x 2 putts each = 36 strokes.
Usually, more strokes are 'lost' on the green than on the rest of a hole. So your goal should be to only make 1 or 2 putts on the green.
Avoid the hazards - like rough, and sand.
Hit tee shots to the fairway, or on par 3's to the green. Hit approach shots to the green.
If you do wind up in a hazard you want to make sure your next shot is from short grass - either fairway or the green.