I have mine on the floor but there are folks who have mounted it on a shelf on the wall next to their machines. I’ve seen several photos with that approach.
Early on I was at @ctgolfer 's shop and he had it mounted on the wall about 5ft up and hooked to the table. It’s handy for getting at the front panel for settings and keeps it well away from any water splash. I’ll be doing that in my next workshop.
Right now I roll the table into the center of the garage to use it and back against the wall to store it so I can’t mount the plasma unit in the wall.