#18: Try Not to Be Terrible
I remember reading somewhere that flight attendants are assessing the passengers as they board the plane, keeping an eye out for anyone who looks like they’re going to be trouble—super drunk, super loud, super-aggressive, and so on. (Which is why I’m over-the-top friendly and chill when I board the plane.)

I think people forget that flying on a plane isn’t a right—you’re on a private vehicle owned by a private company, and if they think your loud, drunk self is going to cause a problem, they are well within their rights to say “Never mind, we don’t want you on our plane.” So maybe watch your behavior when you’re on an airplane.