Do not use nail polish or cheap spray paint from your local auto parts store that guarantees a match. People fail to realize that a car's paint job is sometimes the most expensive component of the car. You could spend thousands repainting your car entirely. Don't cheap out on your paint.
Head over to
Paint Scratch and choose your car's year, make, and model and choose your car's paint color. From there you can purchase a paint pen kit. You will most likely spend about $35.00 shipped, but that is still cheaper than a lot of dealerships.
If you go cheap, you may end up making your paint look worse than it did before. Make the right decision first.