Most states give multiple options for returning your ballot. The safest bet is to put it in a drop box or deliver it in person, typically at an election office.
This depends on the state, but many have trackers to see if officials have received your mail-in ballot. Here's how it works.
If you change your mind about voting by mail and want to do it in person, there will be a way for you to still vote. Here's how to do it in different states.