Book on a Sunday
Sunday is the day to book your flights! Expedia have discovered that booking on a Sunday should result in the cheapest flights. For domestic flights however, avoid Monday and for international flights, avoid Friday.
Book your flight in Incognito Mode
Your browser can tell whether you have been keeping an eye on flights and constantly checking to see if it has gotten cheaper and will put the prices up accordingly. You don’t want to fall into the trap of paying more than you should be, so simply turn your browser into incognito mode or open a new incognito window (For Windows, press Ctrl + Shift + n. For Mac, press ⌘ + Shift + n)
Try a flight comparison site
This is a great starting point. These will do all the hard work for you and will compare different airlines to try and find the cheapest flights/best deals. These are not always 100% accurate though, so it is a good idea to check and book through the direct airline websites once you have found the flights you like. They will either match the price or be cheaper!
Check out these sites:
Book around 50 days before the flight
Obviously don’t leave the booking until last minute. The closer to the flight date that you leave it, the more expensive it will be. According to algorithms devised by some airfare websites, around 50 days before the flight is the magic amount of time. Although, I would still suggest booking as early as possible (not ridiculously early) or waiting for special sales to pop up.
Book in August and February
These are known as the early-bird seasons and can include some great deals - travel agents and airlines will go out of their way to undercut each other. With the nature of people booking flights for the New Years/Christmas period, these months are well in advance and prime sale time.
Subscribe to airline newsletters & follow them on social media
This way you can be informed when there is a sale and you will be notified in advance. Deals can often be offered to loyal subscribers first.
Talk to a travel agent
They are experienced in what they do and will know when sales are coming up. They have close relationships with travelling companies and airlines, so they may be able to give you the best deals possible and can make your life easier a whole lot easier. They may just be able to give you a little extra advice to get you started also. They are there to help.
Sometimes connecting flights/stopovers are the way to go
It’s not always the case and can be more of a hassle but it’s worth having a look because if you don’t mind a longer trip, you can sometimes save a bit of cash by catching seperate flights to your destination. One more bonus of doing this, is that you get to stop off in a different country and experience their airport, you might even get a few extra hours to experience outside of the airport. Try different airlines for stopover flights also.