Prepare a paint sample. Determine what type of finish you will create your ceiling. Practice the technique on a portable paint surface such as poster board or styrofoam art board.
Hold the practice piece up to the ceiling to view during different hours of the day, to determine if you like the color and technique. Adjust the sample with different colors or paint techniques as needed, until the faux finish is exactly what you like.
Remove all furniture from the room or move to the outside perimeter, so you have plenty of access to your tray ceiling. Adjust your ladder so you are able to reach the ceiling or set up scaffolding. Place drop cloths on all flooring. Cover any light fixtures with plastic, if necessary.
Stick painter's tape to any areas where the faux finish and another edge meet, such as the wood trim of the tray ceiling. Burnish the paint well to prevent paint bleeding.
Apply the paint to the ceiling surface. Start at one corner of the ceiling and work outwards. Take plenty of breaks to prevent your neck from growing stiff or tired. Continue to follow the faux finish technique you practiced on your sample board. Keep in mind, the same materials and hand motions must be used in order for your sample board and ceiling's surface to match.