How do you remove paint that got on ceiling?

Get it slightly wet, and it will scrape right off. Don't soak it, otherwise you may damage the drywall behind it, but if you get it slightly wet, it will pretty much fall off. I saw a popcorn removal tool at Lowes that is a square type blade thing that has an attachment that holds a trash bag. This tool would eliminate quite a bit of mess. Maybe even with the tool you wouldn't have to get it wet. Trial and error.