Most cups are not cut on a flat surface, but are on some sort of slope. The key to making putts is reading the slope, so you can diagnose the angle or direction the golf ball will enter the cup from.

You can find the answer by looking at the hole.

Imagine over-filling the cup with water and observing which way the water flows as it trickles through the grass.

Now think of a clock and look at the cup, where the high-point is 12 o’clock and the low-point (or the direction the water is flowing) is 6 o’clock.

If you were looking down at the hole from the 6 o’clock position, you would find the 3 o’clock position to the right, and the 9 o’clock position to the left. Role the ball straight at 3 o’clock from the right side. If the ball has perfect speed, it will curve left in front of the hole and start trickling down directly below 6 o’clock.

The arc the ball travels is the same arc the ball needs to travel to make this putt except you must start the putt to the right of 12 o’clock. The distance to the right can be judged by the distance the ball traveled below 6 o’clock.

Depending on the severity of slope the ball will enter the hole at the 1 or 2 o’clock area. Good putters visualize the path of the ball and have a feel for where the ball will enter the hole based on gravity.