i also have a laptop, that sits atop a breakfast tray when i'm using it... i often have a kitty [usually Pixel, sometimes Chip or Cable] lying on top of my left arm.
usually isn't a problem, as i can still type... but Cable's often not satisfied w/just 'lap time' - she wants to interpost herself between my face & the screen!
My husband banished them from the computer room since Pepper wiped out the hard drive. He also works on his tattoo machines and plays his guitars in that room. He would have heart attack if any of the many guitars got knocked over. Cats love guitars.
About the same way you do. Keep a spot free and put down a fluffy towel for them to lay on. My cats don't cuddle together, so the desk is basically first come first serve. However more often than not, Abby doesn't restrict her spot to the towel. Instead she stretches out and ends up blocking the view of my screen too And Chynna would much rather sit on my graphic tablet in front of my screen than lay on the towel next to it
I mostly use a laptop so Interesting Things can happen when Nikita walks all over it. I try to keep her away from it but if I leave for a bit or don't pay attention something like this happens frequently.
Annie figured out pretty quick that Meowmy will not ignore her if she lays across the keyboard. She's done things - opening programs and windows and closing windows and all kinds of things - that I don't know how to do with the keyboard!
Pardon the mess...too many piles, not enough time!