Check prices starting far in advance of your trip, if you can -- that way you'll be able to gauge the average price and make a better judgment if you think you find a good deal. Dozens of websites claim to help you find the lowest airfare; some are better than others.
Adjust your trip details to find the lowest fare. When you leave, where you fly from and to, how long you stay, and even what time you leave can all affect the price of a ticket. If you can alter any of these you might be able to drive the price down. Check flights into or out of nearby cities; for instance, if you're traveling to New Jersey it might be cheaper to fly into New York, since it's such a large hub.
Avoid flying over the holidays. Flights during the summer (June through September) are also more expensive. Flying during the off season means not only cheaper flights, but less-crowded destinations and deals on hotels and tours.
Use a website like ITA Matrix Airfare Search to discover the cheapest day of the week to fly on. Generally, weekdays are less expensive and Friday through Monday are more expensive. ITA is used by travel agents and is very versatile; you can search for flights leaving through an entire month.
Search on multiple sites. It's good to get an idea of the average price for the ticket; then you'll know when you find a good deal. When you do find one, book it right away. Prices can change in minutes or even seconds. Determine a maximum price that you'll pay for a ticket. When fares drop below that price, get it.
