Best way to hold a rotary cutting ruler

I have carpal tunnel and arthritis and often have trouble using my hands. An internet friend tried to explain the best way to hold my ruler and fabric so there was less slippage. She explained that I need to have my fingers on the ruler and the base of my palm on my fabric. So I sent her this photo to see if that was the way to do it. She said that it was. 

Great! Except that there are days that my hand won't be able to do that. So I will need to get a handle for my ruler and some non-slip dots to help me on those days. So if you want to keep your fabric from slipping and you have no problems with you hands, just keep your fingers on the ruler and the palm of your hand on the fabric. Be careful and do not cut your fingers. Safety gloves may be a necessity in the future.