If you've ever been stuck in the middle seat on an airplane between a bodybuilder and a crying child, you know what torture feels like. Getting a window seat makes getting to the bathroom harder, but it guarantees you'll only have to contend with a seatmate on one side of you, and you'll have a place to rest your head and a scenic view to enjoy. You have multiple opportunities to get yourself a window seat if you act strategically. Don't forget a pillow.
Assign your own seats when you're booking your flight. Most airlines allow you to choose your own seats when you book a trip online. Look for a link saying something like "pick my seats" after you've chosen your flight. Click on a seat next to the window. If you have connecting flights, click on "next flight" so you can choose a seat on that plane as well. If you're booking your flight over the phone, ask the agent for a seat next to a window.
Review your reservation every few days if there were no window seats available when you booked your ticket. The airline's website should allow you to check on your booked flights. Click on "pick my seats" again to see if any window seats have opened up. Click on the seat you want and save your selections.
Check in for your flight at the airport. Check to see if any window seats have opened up as a result of other passengers canceling their flights. If you use a self-service kiosk, you can often review your seat selection and change to a different seat if you wish; if you're working with an agent, ask her to check for you.
Arrive at your boarding gate early if you weren't able to book a window seat. Get to the gate at least an hour before boarding for the best chance of getting a switch. Ask the gate agent politely if there's any way to switch you to a window seat; she may not be able to do anything then, but stay close to the desk. Wait until the end of boarding time to board. Ask again if any window seats are available. If you're one of the last passengers on board, you won't have as much room for your overhead luggage, but the gate agents will know if anyone didn't arrive for the flight, leaving a window seat available for you.
Look for people traveling alone around you on the plane if you have not been able to score a window seat. Ask each person if he or she is willing to switch seats with you. You may not get any takers, but it doesn't hurt to ask.
Book your flight as early as possible. Window seats are in high demand and are often the first ones to get filled up.
If there aren't any window seats available when you're choosing your own seat, pick an aisle seat if possible, since this will be more attractive to fellow travelers if you try to trade seats.
A few airlines, like Southwest and some airlines operated in foreign countries, don't offer assigned seating. If you're traveling with one of these carriers, stay as close as possible to the boarding area. As soon as the agents announce you can board, head to the back of the plane to find a window seat. Other passengers may not want to head all the way back there, leaving you a better selection.