Faded paint is oxidized paint. The UV rays of the sun have broken the mechanical bonds of the paint.
What you generally need to do is paint the plane with the base color but with white added to it to reduce the intensity of the paint. You will need to use lighter shades for the most faded sections, like the tops of the fuselage and tops of the wings and stabs. (Remember to do the same for any decals or markings as well; perhaps easiest to apply these early, and 'fade' everything together.)
As a possible alternative, model train hobbyists suggest using a wash of 1 part white paint to 10 parts thinner, air brushed on in barely perceptible layers until you get the look you're after. As always TEST, TEST, TEST before trying anything on your model.
As far as photos...you might do an image search for 'AMARG,' 'Davis-Monthan' and 'Boneyard'; all those refer to the US military's huge facility near Tucson where whole fleets of out-of-service aircraft are stored...on desert hard-pan under the baking sun...pending reuse, redistribution, parts salvage and/or eventual scrapping. Good 'bird's-eye' photos may be tough to find, but they'll convey a superb idea of what the sun can do to painted aircraft surfaces.