I printed mine with 20% gyroid infill and three shells. Does not require support.

UPDATE July 11, 2023: I have had a couple of these printed in PLA begin to crack and sag at the point where the armature connects to the back. If you're using PLA, up your number of walls to 5 or 6 and use more dense infill (40+% gyroid or honeycomb). I also recommend increasing your bottom thickness to several millimeters so that the solid infill section extends into the curve of the armature. Or, just print in PETG or ABS. 

Use drywall anchors if not screwing directly into wall studs.