Included is a PDF file with printables for the following gestures:
One finger means "Help!"
Two fingers means "Restroom?"
A pencil held in the air means they need to exchange pencils or use the sharpener.
I indicate to my students whether they have permission to do their requests by simply nodding or shaking my head. I have told them in advance that a "no" just means "not now," and that I will let them know when they can go ahead and use the restroom or sharpener.