>>95908900
Find photos of the sort of metal & finish you are going for. Look at the colors in the metal (like brown, dark blue, and a slightly desaturated teal in this image). Paint the surfaces with those colors and push the saturation, and do some volume highlights. You don't really need to do any blending or be clean for that step. Then do a very light drybrush of leadbelcher or similar, and do edge highlights with a brighter silver.