Assume you mean cleaning the back side. If in a hurry I simply fold a micro fibre cloth wetted with plastic cleaner. In extreme cases but not removing to clean, I may wrap the cloth around a tongue depressor stick.
Removing them is best way to clean, but a bit of effort.
I have ridden with and without them installed. Ultimately have them installed.
A friend, while we were doing other stuff to his Spyder, asked about this too. My suggestion was to scuff the backside with Scotchbrite then wash clean. Wipe down with Iso Alcohol and spray paint the backside black. This gave a sort of black mirror look when seen from most angles and cleaning now is not a concern.