Usually by check or money order. In prison they open all mail, so you should leave a note to the person who is to recieve the financing so that they will be aware that they recieved it. A money order would be a lot safer so that your account number is not made available to anybody. On the money order write the receivers name. Your address (or PO Box......a lot safer) will be placed on the money order. Keep your stub to the money order for proof of purchase. Best Wishes!