Blot the oil, if it's fresh, with a folded paper towel. Do not rub the oil or you will spread the stain.
Spray the stain with WD-40. Allow it to sit for 10 minutes, or up to 30 minutes if the oil is dry and set in.
Sponge the stain off with dish soap and a small amount of water, then rinse well with a wet sponge. If you're cleaning an outdoor stain, such as a concrete driveway, rinse the area with a hose. Allow the area to dry.
Spray with more WD-40 if residue from the oil stain remains. Allow it to sit for 20 to 30 minutes, then rinse. Repeat as necessary,