I make shelves for my cats out of 1" x 8" pine plank and carpet. The planks are cut to 2' lengths and the carpet is glued on top using a spray adhesive. The carpet is wrapped around and stapled on the bottom. I use L shaped brackets secured to the wall using threaded zinc drywall anchors. My cats love them!
Video by OutdoorSavannah featuring Raja the Cat. Raja is a savannah and bengal cat.