This is a shower head holder I designed in Fusion 360 and printed. It holds the shower head lower for my kids, so the water isn't falling on them from such a height. It clips onto the shower caddy very securely. It's measured precisely to the size of my shower caddy though, so you'll probably need to adjust that.

http://a360.co/2G9M3wH

That's the fusion 360 link if you want the original and not just the STL.

It's designed to be easily printable. The open section of the holder should face upward, and it needs minimal supports.