If you're looking to buy cheap airline tickets online, there are a few strategies that can help you get the best deals. First, plan and book your tickets in advance, as this can help you secure lower prices. Try to be flexible with your travel dates and times, as off-peak fares are often cheaper. To compare prices across multiple airlines, you can use fare comparison websites such as Skyscanner, Google Flights, Kayak, or EbookTrip and set up price alerts for your desired routes to monitor fluctuations and book when fares drop. Another tip is to consider flying with budget airlines and keep an eye out for promo codes, discounts, and special deals offered by airlines or booking platforms.