Color can set the mood in a room. To make a space appear larger and the ceiling higher, pick patterns with cool-color backgrounds, such as green, blue, or violet. Soft cool colors suggest tranquillity, while intense cool colors are fresh and dramatic. Warm colors -- reds, yellows, and oranges -- live up to their name and actually make people feel warmer. These are a popular choice in colder climates and also work well in north-facing rooms. The more intense the color, the more excitement it will give to a room.