Rolled paper. This one is made with scrapbook papers, but it's also a great idea for left over wrapping paper! Can't get much easier than this!
make a collage, put a stencil in place over it, paint over everything, remove stencil.
mommy is coo coo - how to make a two-seam infinity scarf
Elmer's glue on canvas. Then paint the whole thing one color.