(a) At any time after receiving an official absentee ballot, but before the day of the primary or election, except electors who are confined to a hospital on the day of the primary or election, the elector shall vote his or her absentee ballot, then fold the ballot and enclose and securely seal the same in the envelope on which is printed "Official Absentee Ballot." This envelope shall then be placed in the second one, on which is printed the form of the oath of the elector; the name and oath of the person assisting, if any; and other required...