Fares change constantly based on demand, seat availability, and how far ahead you're booking. A handful of habits consistently help, even without any special tools.
Be flexible on dates
Shifting your departure by even a day or two — especially off a weekend — can meaningfully change the fare. If your trip allows it, use a date-range or "cheapest month" view instead of searching one fixed date at a time.
Search in private/incognito mode
Whether or not prices genuinely rise from repeated searches on a specific browser, booking sites do personalize results, and cached prices can be stale. Searching in a private window with a cleared cache is a low-effort way to make sure you're seeing a fresh, unbiased set of fares.
Compare nearby airports
If your origin or destination city has more than one airport within reasonable reach, price each of them separately — the difference can be substantial, and the extra ground transport time is often worth it for the savings.
Set price alerts instead of checking daily
Most major booking sites and search engines let you track a specific route and get notified when the price drops, which is far less effort — and less tempting to book too early — than manually refreshing search results.
When you're meeting someone else
If you're coordinating with a second traveler from a different city, the cheapest flight for each of you individually isn't automatically the best combined choice — a slightly pricier flight that actually lands near the other traveler's arrival time can save an entire extra night's hotel stay. Comparing arrival windows across candidate meeting cities, not just ticket price, is the more useful frame for that kind of trip.