…make them like this. Clever, humorous, and polite. Signs like this are the best because there’s added value. The reader takes something else away from the sign other than the primary message.
Kudos to Rochelle for the inspired sign. See her post “Library Flyer: It goes to 11” for her take, and a link to a Word document that you can download to have your very own template to alter! And importantly, are there really enough Bears fans in Wisconsin to argue loudly with Packers fans?