Call United Airlines at 1-800-864-8331. Give them the dates and times of anticipated travel for the person that the voucher will be transferred to. You can also have the person whom the voucher will be transferred to call the airline if you don't have the exact details of their trip.
Confirm the dates and times with the reservation agent and give them the voucher number along with the purchaser's credit card number. They will take the voucher amount off the cost of the ticket and they will give a confirmation number that will hold the itinerary for 24 hours.
Present the voucher and the itinerary confirmation number at a United Airlines counter within 24 hours of the booking. The person whose name was originally on the voucher must be present at that time, however it is not neccessary for the transferred party to be present, making the process completely doable if both parties live in different places.
