light over dark: if you don’t do it right, you will see your old dark colored paint bleeding through your newly applied light color paint. Here’s what you need to do to ensure proper coverage:
First, buy a primer/sealer that serves as a stain blocker and apply it onto the wall(s) that are painted in the dark color. This ensures that the dark color does not bleed through.
Secondly, apply the the lighter color. Apply this using 2 coats and you will
be all set!