Ideally, the Compare and Contrast diagram should include three comparisons and three contrasts. It must, however, have at least two comparisons and two contrasts. The circles in the Venn diagram should be very large so that all information fits within them and overlaps with them. Once all of the information has been mentioned into the Compare and Contrast diagram, it is good to color each circle and the overlap area a different color. A Venn diagram is easier to read when three colors are used to "separate" the information.