Fill in the name of the payee. Go to any Post Office location.Take cash, a debit card, or a traveler's check. Fill in the recipient and your address; for bills, include an account number; sign it; keep proof of payment. When filling out a money order, you'll need some basic information, such as the recipient's name and your address. The original detached money order customer's receipt for the original Money Order. Fill out PS Form 6401 (Money Order Inquiry). 1. Fill in the payee's name. Put the payee's name on the line labeled "Pay to the order of" or "Pay to. Fill in the recipient's name.