Same as the others. We don't use ours much either but whenever we do, we be sure to wipe it down after use. I shudder at those who have caked on food inside the microwave.
I keep my food covered in order to not splatter on the microwave. Now there is the few times other people use the microwave and don't understand that. So I have to clean it maybe the next time I use it. I usually don't realize it got splattered until I need to use it, and I just go ahead and use it that time, then clean it the next.
I clean with disinfectant wipes, water after, and then dry it with a towel.