Yes, please clean up after yourself
If you want to use the kitchen to prepare snacks or meals, you should know how to tidy up afterward. Nobody wants to have to spend time cleaning up someone else’s mess. We’re all grownups here, and we shouldn’t expect others to clean up after us as if we were children.
People who don’t know how to clean up after themselves are one of many people’s pet peeves. If you’re tired of reminding others and wish to put up a sign identical to this, we’ll understand.