[Paul Stenning]

I would normally go for a cream or beige colour, as it doesn't look as "new" as a bright white. For some sets, a gold or bronze colour is more appropriate. I normally use enamel paint (small tubs sold for painting plastic models). Like you, I don't worry about getting paint on the surface of the knob. I clean this off with Brasso after a couple of hours. Enamel paint and Brasso are normally OK on plastic knobs too.