I'm in Ohio... In Ohio, any one can vote by mail/absentee, though originally designed for military and those whom cannot make it to a poll station they opened it up a long time back to pretty much any one in the state whom wants to .
All you need to do for mail/absentee balloting is go to the state board of electors web site, download the application in PDF form that they have on a sub page, and fill out and mail it to them (the correct address to mail them to is on the board of electors site)... you need to do that for each election separately and cannot combine them into one and warns you not to try.
So in March of each year (I do it that early to get it over with, you do not need to do it that early in Ohio), I download and print 3 copies, and mail in the application for the Primary(nominally in May), the Special(nominally in August), and the General(nominally in November) elections.
Since they have it on file I vote that way, they know to automatically send them as soon as they are ready. That is normally just under a month before the in person voting date. So the soonest I could have gotten mine this time around was October 12th, the date they started mailing them out... Mine actually arrived on October 14th, filled it out that night, and mailed it this morning when I went for breakfast.
So all the election stuff for myself and my mother is all over with.
The benefit of mail/absentee balloting is no trip to the polls, no long lines, no groups of people yelling things at you to support, no standing while filling out the forms or confirming of identity. Just calmly and quietly sit in the kitchen at the table or living room coffee table and go through the options, and look up anyone do not know. All it costs is a stamp/envelope to mail the application, and a stamp to mail the ballot.
Now that it is mailed, I can actually check the board of electors web site for the status, they have a page where you can enter your name to see your ballot status. So in a few days I'll check to see if they got it, and normally once it is stated received, it may take a day or so to then show as processed and counted as valid...
Pretty painless.