1. Check your reservation.
All you need is your confirmation number. Make sure the times and even flight dates or airport haven't changed. You can do it online or by calling the airline or online travel agency. If your flight has changed, review the flights you're booked on and call or go online to try to find better options if those don't work.
2. Pay attention to emails from your airline(s).
Sure, it might be another pitch for a fare sale or a frequent yer credit card, but it could also be notification of an important flight change or cancellation.
3. Don't wait until the day before or week of your trip to reconfirm.
Your rebooking options will be even more limited if your flight has been changed or canceled. Worse, you could miss the new flight the airline put you on or be stuck at the airport for hours if it's later.
4. In the worst-case scenario, be prepared to shell out more money to buy a ticket on another airline if your travel dates or times aren't flexible.
Airlines are required to refund your money if they cancel a flight or change it significantly, but that might not cover the price of a ticket on another airline, especially last minute. My sister, a teacher, had to shell out an extra $600 for her family to get home on Labor Day because Southwest canceled their (very cheap) flight and couldn't get them home until Tuesday. In dire cases, you can ask the airline to put you on another airline, but Southwest doesn't do that, and other major airlines prefer not to if other options on the airline are available. 5.
Build some flexibility into your travel plans if you're buying tickets. If you have to be at your destination or home by a certain date for work or school, don't cut it close with your flights in case there are changes or cancellations.