Diamond is able to get out onto the "deck" by himself, but can't get from there to the "loft" (on top of the cage). To help him climb, I made temporary steps for him. Once he can grip vertical bars with confidence, I'll remove them.
I found a scrap of fine furnature wood (I think it's cherry) that's a square stick of the size you see. So I cut four lengths and drilled holes. That's making a long story short: Find what kind of ¾″ wood screws I have on hand, drill pilot holes for the "nut" side so the wood screws will grip their threads nicely; drill larger holes on the other piece and counterbore the 45° angle of the flat-head screws so they just lie flush; find correct sizes of bits and fiddle around with that a while; lose the set screw of a counterboring tool; measure twice cut five of six times
; figure out how to clamp it while tightening the screws, etc. IOW, typical DIY workshop playing
I found a scrap of fine furnature wood (I think it's cherry) that's a square stick of the size you see. So I cut four lengths and drilled holes. That's making a long story short: Find what kind of ¾″ wood screws I have on hand, drill pilot holes for the "nut" side so the wood screws will grip their threads nicely; drill larger holes on the other piece and counterbore the 45° angle of the flat-head screws so they just lie flush; find correct sizes of bits and fiddle around with that a while; lose the set screw of a counterboring tool; measure twice cut five of six times
; figure out how to clamp it while tightening the screws, etc. IOW, typical DIY workshop playing 
