The Around the Clock drill is an excellent way to read the greens when practicing your putting and to understand how the slopes on the green will affect the amount the ball will break.
Find a suitable hole on the practice putting green.
Position 12 tees around the hole at approximately 10ft away from the hole.
Place 12 balls next to the tees.
Set yourself up on the 1st ball and strike the putt.
Then move around the imaginary clock face trying to hole as many putts as possible.
You will see that the ball breaks in different directions.
Once you have completed this try again to beat your best score.