Since these are made from heavy duty cardboard, they are not designed to hold a heavy load.
First, find the cement form at the lumber yard. This one was 4' long.
Second, saw them into 6-8" lengths.
Third, sand the edges where they are ragged.
Fourth, use either spray paint or acrylic paint with a brush on the interior.
Fifth, after the inside paint dries, paint the outside of them.
I chose high gloss paint for the look of it.
Sixth, my husband cut out round plywood or mdf (medium density fiberboard) discs to fit on the back of each shelf.
Seventh, He used a staple gun to attach a disc to each cardboard cylinder.
Eighth, I glued a piece of colorful poster board to cover each disc.
Ninth, we hung the shelves with a screw through the back of each cylinder to the wall.
It is a colorful way to display and store my yarn.