The 60/30/10 rule refers to the colors that you use when decorating a room. You should choose three colors for your color scheme. The first color is the primary color that you will use in 60 percent of the room, making it the dominant color in the room. The next color is the secondary color and should be used in 30 percent of the room. The third and final color is an accent color. It should be used sparingly in only 10 percent of the room.