Some great tips so far,
I am thinking your saying the colored part you want old looking,
Any way here's what I do for the old leather look,
I start with the airbrush spray a even light coat over the hole piece then spray a darker coat around the edges, let dry buff with a rag, then I take a rag and take a little dark brown stain and rub it off on a paper almost tell there's nothing left on it, then I rub the edges of the piece lightly let it dry the buff, last step take some black dye on a rag and do the same as the brown dye heavy on the very edges, let dry buff apply finish then I might rub on some antiuqe if needed or wanted.
With paint I apply it let dry the rub some denatured alcoholl then a rub with antiuqe.
Josh
Bad spelling on my iPhone