Q. Where can I find absentee voting guidelines for my state?

Absentee voting (aka "mail-in voting" and "by-mail voting") is conducted by mail-in ballot before the day of the election. Vote.org collects every state's absentee rules as part of their state guides to deadlines, dates, and rules. 

For, Shelby County residents, the Shelby County Election Commission  also has information on Absentee Voting.