You also must fill out a money order correctly, otherwise it will have to be canceled and refunded, and then repurchased. AdvertisementAdvertisementBefore you go to buy a money order, make sure you know what types of payment are accepted. The amount will be printed when the money order is prepared by the issuer, but you'll fill in everything else. Fill in the recipient's address and your address, if required, depending on the type of money order. Sign the money order in a \"Signature\" or \"Purchaser\" field, if one is required.