A few things I've learned to keep it tolerable.

1. Be nice to the FAs.
2. Be nice to the GAs.
3. Be nice to your fellow passengers. Even the goober who is trying to figure out how his steamer trunk full of lead bricks is going to fit into the overhead bin.
4. Bring your own eyeshades, toothbrush, toothpaste, and headphones. Better to have them and not need them than need them and not have them.
5. Don't sweat it if they are out of your first meal choice. It probably wasn't that good anyway.
6. Always, put Baileys on the ice cream. Mmmm..... Two exceptions - first, with the almond ice cream, amaretto is better, and second, don't try this in coach. You might think that the paper cup will stand up to this, but it won't.
7. Join the RCC (or, if flying internationally, be a *G). It's not perfect, but it sure beats hanging out in the concourse. Then be nice to the staff.