Unstringing yes, but NO propping. Could damage your tips.
Build a two piece mount of rubber. Basically two wedges. Mount them so they can pivot. With the bow limb placed between them, its weight will pull down and cause the rubber to clamp together, suspending it. I can draw a diagram if you need it, but its a pretty simple concept.
This is how I use to store mine, but now my closet is big enough, I can lay it flat on the top shelf.