Here's something I drew up for myself that may be useful to others:
A very crude, simplified X-Wing paint guide blank.
This is a little bit like "paint by numbers."
Pick your canonical bird, or go freestyle.
I know all the panels aren't there, and this is very much a quick and dirty drawing. I just thought this might be useful for general paint scheme planning and playing around.
Attached is a rasterized image, a PDF, and a hypothetical example.