Sun Baked Look

One of the quickest ways to make your paint job look like it's been sitting outside in the sun for months on end is to reduce the chroma (strength) of the paint color. You can do this by adding 10%-30% white paint to your paint before brush/airbrushing the paint onto the object.

If you did not add white before painting the object, sometimes a light mist of white spray paint can achieve the desired result, but this is only recommended as a last resort.