If you have an event to go to, allow a window of a few days either side to give you as much choice as possible. Air New Zealand's site allows you to see at a glance a range of the cheapest fares three days either side and invariably I grab one of their alternative suggestions.
3. Fly to secondary airports
Some airports add huge departure and arrival taxes (I'm looking at you London, whacking about $400 on a ticket). For travel to Britain consider flying into Manchester and out of Paris or somewhere else in Europe. If you are in the United States the bigger cities offer more choice, so you'll find Los Angeles to New York, for example, will be more competitive than secondary airports.
4. Try different routes
If Paris is your final destination, for example, think about various routes and airlines that might offer better deals. I would look at Singapore Airlines and Emirates for the sheer choice of destinations they fly into. China Southern is also worth a look as they are often more price competitive and are making a bit of a splash in the market right now.
5. Earn air mileage points everywhere
Make sure you are not only an air points member, but hook up your weekly spending too and before you know it you'll be swimming in free flights. Certain credit cards, supermarkets and retailers are hooked up with Air New Zealand Airpoints. Some banks also have deals to tag your mortgage on to so you may never need to pay for a domestic flight with real money.
Click here for Megan's blog on saving money while travelling.