The overall contour of the green can be assessed from 50-100 yards out. It's a fact that a ball will roll away from mountains and towards the ocean; so if there is a hill near the green the ball will roll away from it. If there is a lake near the green the ball will roll toward it. The Grain affects the roll! Grain is mostly seen on the fringe of the green. Putts with grain roll faster and farther, against the grain slower and not so far. Check from both sides of your ball as well as behind the ball when lining up. The appearance of the grass shows the grain. If it looks shiny the grain is away from you. If dull, the grain is towards you.