I love my portable design wall, which leans just enough so practically nothing ever falls off. I almost never have to use pins. Just buy the 2" think pink styrofoam insulation that is used in basements, etc. (home depot) Cover with Flannel. I made covers like giant pillow cases and covered two of the 4x8 sheets of foam. then hand whip stitched together on one edge. I covered them so that one side is light blue other side is dark green. nice to switch depending on what value of blocks you are auditioning. so they stand out.