Paint the ceiling a light color using a semi-gloss product. The combination of the light color, such as eggshell, and gloss gives the illusion of height. You may select any pale color, as long as it is lighter than the walls.
Color the walls of the room in a pale, cool shade. Look for tints that are blue or green.
Apply a trim around the ceiling, and paint it a dark color. The dark trim will draw the eye upward and give the impression of space. Crown molding is especially effective when adding depth to a room.
Paint dark vertical stripes on one or more walls. The stripes will make the walls appear taller.