Log into the Qantas website or mobile app using your account details and booking reference. You can view, change, or cancel flights up to 1 hour before departure for a fee. Upgrades, seat selection, and extra baggage can be added for a charge anytime before travel. Changes and cancellations for award flights can be made for free up to 1 hour before departure. For further details about Manage Qantas Airways Booking contact the customer service at 1 (800) 227-4500 or 1 (888) 838-0309 (OTA-Skip Waiting). Or visit the Airwaysmanagebooking site.