BE PREPARED TO WAIT. This sounds simple, but may be much more complicated that you might think upfront. Boredom, personal hygiene, warmth & comfort, communication, and hunger are all issues that will need to be addressed. We'll deal with each of these one-by-one in the following steps.
BOREDOM: Given the fact that you could be sitting and walking around the airport for days on end - plan accordingly. Bring a book or two. Don't bring a short read and don't bring something you've only got 50 pages left of. Or if you do, have a plan B for once you finish. But reading will only kill so much time. Bring some simple toys - cards, dice, travel games (scrabble and chess are my personal favorites). Even if you're traveling alone, you'll quickly learn who your fellow stand-by victims are.
PERSONAL HYGIENE: Pack a "ditty-bag" of personal hygiene products. Soap, facial cleanser, deodorant, tooth paste and tooth brush, hair brush, razor and shaving cream. The list should be comprehensive. You may even reach a point where you're willing to shampoo your hair in an airport john. Be prepared. And remember to pack it all in 4oz bottles or smaller - otherwise you'll lose all your supplies at security. Under the personal hygiene category also falls the extra sox and undies. Put a few back-ups of each in your carry-on - and a ziplock back to toss your dirties in.
WARMTH & COMFORT: Get a small pillow or a neck pillow that will stow in your carry-on. Sleeping is so much easier with a head rest. Take a small blanket as well. Without these necessities you may find yourself sleeping on a hard floor. Bring along a hat or a eye-shade - trying to sleep under bright overhead fluorescent lights can prove impossible.
WARMTH & COMFORT (Cont): As you walk around the airport from gate to gate - getting bumped from one flight after another - pay attention to which gates have seating with no armrests. Every airport I've ever been in has such seating - but often these seats are only in 1 terminal or a handful of various gates. Many airports close down after 9 or 10pm, so getting to these benches first is a huge bonus.
COMMUNICATION: The cell phone is automatic - but what about the charger. I once relied on the airport having charging stands available and ended up begging for change to use the pay phones. Pack your charger in your carry-on - remember that everything you pack in your checked luggage is no longer with you when you get bumped. The phone, if you can charge it, can also provide entertainment to stave off a potentially fatal level of boredom.
HUNGER: Pack snacks and bring cash. You may be in this airport for awhile - days even - and having 1 packet of crackers and a banana just won't cut it. Plan to bring some fresh fruit but also bring food items that won't spoil in 2-3 days. The cash becomes a necessity if you hope to use vending machines. This may be your only option if you are too late, or can't afford, to eat at airport restaurants.
MISCELLANEOUS TIPS: Don't have a deadline - or least plan deadlines around a 2-day delay at the airport. Don't even bother trying to fly stand-by on Holiday weekends, unless you are with an airline employee. Weekends should be avoided anyway - fly out Thurs and back in Mon. Your chances are much better. Don't give up on a flight just because the numbers look bad - these numbers change constantly and all you need is one connecting flight to miss - and you're airborne.
Don't even bother on Holiday weekends unless you are the airline employee or are flying with the employee.
