Collect your confirmation number and the original flight date. Have the date you wish to fly available, along with any other possible dates. It's best to be as flexible as possible when working with the airlines.
Call the airline and explain that you won't be able to fly on the original ticket date. Tell the customer service representative on which date you want to fly.
Give the airline representative an alternative date and time if she is not able to get you a flight on your first choice for a new date. She may offer you another option, which you may or may not choose to accept.
