Mailing under section 1947 shall be accomplished by complying with the following:

    (1) Enclosing a copy of the order as above described in a sealed envelope with first class postage fully prepaid addressed to the defendant at the address hereinbefore required, on which envelope there is listed a return address to which it can be returned in case delivery cannot be made.

    (2) Depositing the envelope and contents in the United States government mail.