I'm not familiar with the kit, but did it come with a set of decals? You might be able to find the color scheme for the plane by doing an image search for Sopwith Camel color schemes, and hopefuly find an image that has markings that match the decals in your kit.
Of course, you'd still have to research what the colors are and how to replicate them with whatever paints you are using. Sorry, that's all I can think of.
Cheers, Mark