By Ashley Lusk, CNN

(CNN) -- The "I Voted" sticker may look the same, but make no mistake: in 2020, voting will look very different. The best way to make sure your vote is counted is to have a plan.

"Don't wait to register. Don't wait to check your registration. Don't wait to request your ballot. Don't wait to return it. Because you want to make sure that you leave nothing to chance in this very, very important moment," said Tammy Patrick, senior advisor to the elections team at the Democracy Fund.

More Americans than ever will choose not to vote in person on Election Day this year, because of the ongoing coronavirus pandemic. Depending on their state, some will opt for early voting, casting their ballots at polling places in the weeks ahead of the election, but many others will vote by mail.

The history of voting by mail

Voting by mail isn't new.

According to Patrick, Americans have been casting their vote through the Postal Service since the Civil War, when President Abraham Lincoln wanted to ensure that soldiers who were away from home still had the ability to vote in the election.

And although tens of millions of voters typically vote this way in every federal election, this is the first election in American history where more than 80% of all voters will be eligible to vote by mail.

The process for requesting to vote by mail varies by state and to make things even more complicated, each state has different processes. Voters in some states automatically get mailed a ballot, and voters in other states need to apply for a mail-in ballot. Check each state's rules here.

Ensuring your vote is counted

First, make sure you request your ballot early -- many states have a deadline for requesting ballots to ensure they arrive on time. And if Election Day is drawing near and you still haven't received your ballot, check in with your local board of elections. Look up state-by-state rules using CNN's voter guide.

Patrick points out that in some states you can even request a ballot up to the day before the election.

Then, double-check the rules about how to fill out the ballot.

"[One reason] that ballots get rejected is because of a lack of signature or the signature that doesn't match. That's where you just want to make sure that you sign it where you need to," says Patrick. Some states even require the signature of a witness.

Mail-in ballots can typically be returned to local officials and dropboxes as well as by mail. Traditionally, the US Postal Service has recommended you mail your ballot at least a week before the election.

And that's it. Request your ballot early. Read the submission instructions closely. And return it in time.

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