General Travel Tips for a more enjoyable flight

If your seat mate starts to talk your ear off, pretend you're sleeping.
If you're traveling with a partner, cross pack with one another. This way, if one of the bags is lost or stolen, you'll still have some of your stuff.
Bring books! Audio books, regular books, whatever suits you.
Pack your own neck pillow especially if you're taking a longer flight.
Wear comfortable slip on shoes. Your feet may swell, or you may just want to take them off while sleeping.

A Few Tips for Budget Travelers

Tip #1: Travel light. Airlines are charging for everything now, and if you pack heavy, you may get bombarded with an extra bag fee or two.
Tip #2: Plan your trip in advance. Booking tickets at the last minute usually tends to be more expensive, and you'll miss out on deals.
Tip #3: If you're taking a trip that is going to take more than a few hours, book it through the night so that you can save on having to get a hotel room.
Tip #4: Consider the exchange rate if you're traveling abroad, and try to cash in your money when it'll benefit you the most.
Tip #5: Ask about deals and free upgrades. You never know, some hotels have them and just don't bother to tell you about it. There's never harm in inquiries.

Relax! You didn't go on vacation to wake up at the crack of dawn with a jam packed itinerary. Give yourself time to deviate from routine. The less you see, the more you'll take in.
Even when you're looking to travel cheap you should allow yourself at least one upgrade. Whether it's your hotel room, rental car, or flight, do something for yourself and don't feel guilty about it!
Be spontaneous. You don't have to reserve and plan everything. Last minute travelers are rewarded with great deals, not to mention that incredible feeling of freedom.
Make an effort to talk to a local. They know more than you and your guidebook.
Try the local food. Find a street cart and order the locals' favorite. You'll save money and you'll leave the place knowing a bit more about the culture.