Click anywhere to place a point. You can also click and drag to see a preview of what it will look like before you place it. You can also drag placed points around. All points will connect to all points. Press the Spacebar to delete a point you are near. Press P to place points at a certain X and Y. Press C to clear all points.
----------UPDATES---------- 10/02/2017: You can now drag points. You can now delete points. You can now place points by entering X and Y. You can now delete all points.