I drive by the El Paso County offices every day on the way to work so I fill out my ballot and drop it in the drop-box (which I guess is functionally pretty close to "mailing it in").

I hate our mail in system because its just asking for abuse and fraud, but I wouldn't wait until election day to go vote because one way people will cheat is to submit a ballot in your name so you could easily get to the polls and find out you've "already voted".

Vote early and often.