For this scene I'm using the local colours (so my skin and hair pallete, and the clothes colours I chose to fit for this scene) and then putting a multiply layer of purple for nighttime, and an overlay layer of yellow for firelight. I didn't do this for the background though, I just painted that as is :).
(I also always have a paper texture overlay on the whole page, and more texture is added with the noise brush used for the firelight overlay)