Add a squirt of grease-fighting dish soap to a small bucket of water. Dip a sponge or rag into the bucket. Rub the scratched areas with the rag or sponge to remove grease, oils, dirt and grime. Dry the scratches with a rag.
Match the sprayed-on color to the existing color on the countertop and buy a can of spray paint if you do not have paint left over from the original project.
Mask off the chipped or scratched area with light-tack blue painter's masking tape. Place the tape as close to the scratches or chips as possible. Place newspapers on the floor and around the masked-off area to protect the surfaces from over-spray.
Spray scratches and nicks lightly with the spray paint until paint covers the scratches or nicks. Remove the painter's tape. Place an artist's paintbrush in the center of the scratch or nick and pull the brush outward to blend the paint with the existing countertop. Continue to pull the paint from the center toward the outer edges from all sides of the damage until the lines between the existing paint and the new paint is not obvious. Work quickly -- Krylon paint typically dries in 15 minutes.