There are two places where you consistently have to remind people to play nice with others, stop screaming, and keep their hands to themselves. One is preschool. The other is an airplane.

It's not news that the general standard of behavior on airplanes has declined in recent years. In fact, there's a whole social media campaign devoted to it. Passenger Shaming, started by former flight attendant Shawn Kathleen, aims to shine a light on the grossest, rudest, and jerkiest behavior on airplanes by posting photos of these airborne offenders for the world to see. The goal: to end bad airplane behavior forever.

"I want to bring the [shameful] behavior to the attention of people who may not think it's an issue until they see someone else doing it and they see the response it gets [on my site]," Shawn Kathleen tells Yahoo Travel. "Maybe you'll see Passenger Shaming and say, 'Oh, s---, I do that; it never crossed my mind that I shouldn't clip my toenails on an airplane.'"

Sure, some people may bristle at the public social media shaming of unsuspecting air passengers. But the thing is, it's really easy to keep from getting passenger-shamed: Don't do anything shameful.

So if you want to up your passenger-etiquette game — or at the very least, avoid being made fun of on social media — here are some things you can do to keep from being passenger-shamed.