Open the RAV4's hood. Locate the back of the headlight assembly, just behind the headlight. You should see a ring-shaped plastic cover.
Turn the locking plastic ring clockwise about 1/2 inch and it should pop off.
Remove the rubber grommet covering back of the headlight. Simply pull it out of the headlight assembly.
Depress the spring latch holding the bulb in place behind the headlight. This is a wire latch that looks somewhat like a bent paper clip. Press it down and move it to the side, away from the light bulb. It should come free and flip open, freeing the bulb.
Disconnect the light bulb from the plug. Replace it with the new light bulb, and replace the latch and rubber grommet. Replace the plastic ring cover and turn your headlights on to ensure proper installation.