How can you make the perfect bookcase extra perfect? Try adding some color with wallpaper or even craft paper or contact paper. Not on your books or on the top and sides of the bookcase, but rather in back, where it will frame whatever is on your bookcase, absolutely brilliantly.
This is a super DIY project if you’re dealing with a flatpack bookcase, e.g., the Ikea Billy, since you can take off the whole back and simply cover it, but it’s none too difficult when you have to put the paper on the backing directly. It just means a bit of careful measuring and cutting, and a somewhat more careful application. But, oh, so worth it! See?