Appreciate your fellow passengers as you're going to be couped up together for a fair while...
Don't get drunk and loud.
Don't shout down the aisle to one another.
Don't recline your seat without asking the person behind if they mind.
Don't kick the seat in front or allow your children to do so.
Don't use the seat in front as a grab handle to heave yourself out of your seat.
Try and remain within the confines of your own seats width.
Make sure you have a bath/shower/wash/spray deodorant before flying.
Don't fart/burp etc
Don't use the toilets to do your make-up unless there is no one else queing.
DO NOT pee on the floor in the loo.
Don't assume the person next to you wants to chat.
Don't be rude if the person next to you keeps chatting.
Don't treat the cabin crew like slaves.
Don't have your music so loud that everyone nearby can hear it.
Get your passport/tickets etc out ready before you get to the desk/gate/security check
Listen to the safety briefing and read the card, it is important.
Obey the seat belt sign.
Don't stand in the aisle when boarding, put your bag in the overhead and sit down so everyone else can get by.