Scratches on cars are fairly easy to remove, with a little patience. Most scratches aren't even scratches at all: they're materials rubbed on the car that sticks. This will walk you through how to diagnose a scratch, and how to fix it.
Step 1: Materials
Aerosol adhesive remover
Soap and water
Black shoe polish
Ultrafine sandpaper: 2000 to 3000 grit for wet dry use