Remove the mounting plate from the back of the light fixture by rotating to the unlocked position and lifting up on it.
Position the mounting plate on the underside of the shelf where you would like the light located. Mark the mounting holes with a pencil.
Drill a 1/4- to 5/16-inch deep hole in the center of each marked hole on the underside of the shelf using a pilot hole bit.
Place the mounting plate over the pilot holes and drive the screws included with the light into the underside of the shelf with a screwdriver.
Align the light fixture under the mounting plate and rotate it into the locked position to secure the light to the mounting plate.