Tips to find cheap domestic flights

These tips are almost obvious … but it never hurts to hear them again.
1) First and foremost, plan your trip in advance and you will find much better deals then if you procrastinate.
2) Try to schedule your trip midweek (Tuesday-Thursday) if possible.
3) Better prices are found by looking at one-stop or connecting routed flights rather than just non-stops.
4) Yeah the early-morning and late-night flights don’t fit your schedule the best, but they’re also the cheapest.
5) Use search engines that let you search for flights before and after your desired date.
Be Flexible (Travel + Leisure Magazine)