When booking flights, start by checking all of the possible alternative routes. "If the flight has more than one leg, search the separate legs yourself," the Benders write. Breaking up a direct flight into two or more smaller flights has saved them up to $400 on one trip.
You'll also want to consider all of your airport options. "When booking flights, sometimes it is cheaper to fly into airports other than your final destination, and then take a train or bus," writes Matt Kepnes, travel blogger and author of "How to Travel the World on $50 a Day." "This is especially true during peak travel season or festivals."
Of course, you'll want to make sure the airport isn't too far out of the way and calculate whether or not the amount saved on the flight is worth the extra transport required.