1. Open the photograph of the car and its license plate.
2. Zoom in on the license plate and select the Clone Stamp tool.
3. Hold down the ALT key and select the color around the numbers on the license plate.
4. Let go of the ALT key and paint over the numbers.
5. Do steps 3 and 4 until the license plate is a clean slate.
6. Select the Type tool.
7. Choose a font that looks close to the previous license plate numbers.
8. Type out what you want the license plate to say.
9. You should now have your edited license plate.