I thought I would provide an excerpt here from a Wisconsin government website that details a few things about Absentee ballots. Everyone should be able to find equivalent information for their own states.
https://elections.wi.gov/node/7039
Early September 2020: On September 1, the WEC will be mailing information about voting in November to approximately 2.6 million registered Wisconsin voters who have not already requested an absentee ballot. (See attached.) The information packet will include an absentee request form and a postage-paid reply envelope. Wolfe encouraged voters who choose to vote absentee to request their ballot as soon as possible, whether online or by mail.
September 17, 2020: This is the deadline for Wisconsin’s city, village and town clerks to mail absentee ballots for November 3 to registered voters with requests on file. At 47 days before the election, Wisconsin gives its voters significantly more time to receive and return their ballots than most other states.
October 14, 2020: Your last chance to register by mail or online. Visit https://myvote.wi.gov to complete the registration process in minutes or find your municipal clerk’s mailing address.
October 15 to November 1, 2020: During this closed registration period, you must register to vote in your municipal clerk’s office or at a satellite voting location run by your municipal clerk.
October 20, 2020: The first day that municipal clerks may offer in-person absentee voting in their office or a satellite location. Start dates and office hours vary by municipality. Please visit https://myvote.wi.gov to find your municipal clerk office’s contact information and learn more about absentee voting in-person for the upcoming election.
It is my intention to fill out my ballot shortly after receiving it, take my completed ballot down to my city clerk, call the clerk’s office, wait for the clerk (or designee) to come outside, place the ballot in a mutually observable location while maintaining social distance, back away and observe the clerk (or designee) pick up the ballot, and observe the clerk (or designee) re-enter their office building. You might want to consider a similar tactic if possible. As much as I like the USPS, I don’t trust Trump’s cronies because they’re doing their best to fuck up the works, so I’m not relying on the US Snail.