I am currently battling Carpal Tunnel Syndrome and found it difficult to pull up on the shower diverter knob so made a simple but very useful tool to help. I thought I would share it here in case others have the same problem or know someone with mobility issues who could use the same. It's cut for 1/4' poplar wood but could be from whatever you have.
No real instructions are needed other than to make sure the diameter of your shower diverter knob matches the design, otherwise increase as required