2. Alternative airports
When you're flying into an area with multiple airports, it pays to check out the prices to each one. For instance, when I fly from Phoenix to San Francisco to visit family, I find it's consistently cheaper to fly into Oakland rather than SFO.
Of course, you don't always want to default to the smaller airport. There's a myth that flying into a major hub like JFK or LAX is always going to cost more, but sometimes it can actually cost less. So it always pays to check for each flight.
One good way to do that is with Google Flights. It lets you put in a city or region and then shows you on a map the prices for each airport. You can quickly spot if one airport is going to be cheaper than the others.
Similarly, there's a myth that you can save big if you book a connecting flight versus a direct flight. The Airlines Reporting Corp. looked at 57 million tickets last year and found the average savings was about $1.03. In my book, that's not worth the extra hassle.
However, the ARC did find that a Saturday night stay over could save you big. Again, it comes down to how much of a hassle that is for you.