I put some paint on a sheet of paper and placed it securely in a ziplock back and taped the bag to the floor. (You always want to be as safe as you can with plastic and babies- so obviously make sure you’re paying attention). Make sure that you use light paint so that if it globs up on the page that it doesn’t bust a hole right through the paper- this has happened a few times to us.
Then I let the kiddos go to town moving the paint around. Dutch is always so fascinated with mixing the colors around. When we’re done I take the paper out and let it dry.