Traveling on a middle class salary most likely means you will be sitting in coach... ugh.... I also like to refer to this as legalized human torture. Now I'm 6 feet tall so it's really hard for me, if you're taller I feel your pain and if you are shorter, it's still tough. Here's how I make it through these 10+ hour flights.
-Pajamas, this is the most important thing! Dress comfortably! I don't wear a full pj's, but if you see me on an international flight, I have on gym shorts or sweats, a t shirt or sweater, and flip flops! Dress as comfortably as possible! I leave my wallet, passport, and camera in a secure zipped pocket in my carry on so when I get up I don't have to think about anything.
-Books, movies, music, and whatever other hobby you can do in a little seat. If I know I am going to be traveling in the summer, and my favorite authors are releasing books in spring, I save them for summer, I also don't get to the movies much during the year so it's cool when the flight selections are all things I haven't seen yet. Mp3 player is a must. I like to do art work and sketch, so I bring my sketch pad, anything you can do from the seat that you enjoy doing! Reading, writing, thumb twittling... international flights are rough.
-Sleep, the obvious one right, some people take meds, I prefer to go out the night before, or party all night when I am leaving a country returning to the states. It will take one or two international flights to get your system down, I prefer the exit row if possible, if not an aisle seat so I stick my legs out in the aisle (the stewardess's usually hate me) and rest my head on my coat so as to not interfere with other travelers. My other system is what I used to sleep in grade school, I stack my books on my tray high enough to rest my elbows comfortably, then knock out that way.
-Stretch and meet people, I get up like every half hour when I can't sleep, I try to hang out in the middle of the plane and talk to anyone who crosses my path! Sometimes I can surprise attack them if they don't think I speak their language! It doesn't matter if it's an 80 year old woman or a guy my age, people on flights get bored! It's a good place to chat it up while killing time and getting your stretch on. Who knows you might even make a good connection for the place you are about to visit!
-Your buddy, I so wish more often I had this option, a lot my trips I've flown solo, but having a friend helps so much! Deck of cards, computer game, or just conversation. Can't replace friends.
Hopefully some of this helps! Ultimately it sucks, but just think once you land that's it, you are somewhere you have never been before and are about to see the world you haven't seen or return to your world you know to talk about it.