custom engine painting

Total noob here. I was at a flea market over the weekend and bought a few brass interurban models (probably from the 1970s). To say the paint is bad is quite the understatement. What would be a good resource to use in learning this skill? Louise

Sort of a proof-of-concept, since I didn't want to destroy a "good" locomotive until I knew I could actually accomplish the paint job. I've painted and decaled a number of units in real RR paint schemes, but this was my first go at designing my own paint job, creating the decals for it, etc...

Engine painting Charlie Schulz