How hard to jelq with jelqdevice?

As the topic says, I wonder how hard you need to jelq with the device? Anyone experienced got any advice?

And have anyone used the device in the bath or in the shower?

I currently use a jelq device I built from instructions I found on this site. I wouldn’t jelq any other way, it almost guarantees better consistent contact than can be obtained by hand. This is my opinion only.. I also find using olive oil works beautiful as a lubricant, and is good for the skin.. :)