I was so excited to vote in my local primary election in August. I eagerly researched my local candidates, combed the newspaper for profiles and policy positions, and shared infographics on Insta about voting deadlines. I considered myself a keen voter.

Little did I know that a few weeks after the election I would receive a curt note from the Division of Elections in my state saying that my vote didn't count. (The letter praised my "proof of desire to participate in democracy" — ouch!)

What happened? I was disappointed, to say the least.

I made a simple yet stupidmistake. I thought I did everything right: I printed off my ballot online, carefully making my choices in black ink, remembering to sign the exterior of the envelope and turn it in. But I forgot one crucial step. My local post office, where I submitted my ballot, picks up all mail by 2 p.m. Any mail that is dropped off even a minute after 2 p.m. is not postmarked with that day's date. Instead, it is postmarked the following day. I turned mine in after a busy morning job hunting at 2:15 p.m.

My vote did not count because I turned it in too late.

I felt so disappointed in myself when I received that letter from the DOE. Even though I was volunteering for a primary candidate, they did not receive my vote. How could I have made such a stupid mistake? I was kicking myself for not paying enough attention, for letting my ballot sit on my desk while I interviewed for jobs or worked on my writing. Even though I'm disappointed in myself for not prioritizing my primary vote, I'm glad I learned my lesson and I know better for the general election. I know now that my vote is too important to wait around. Next time I do a mail-in ballot, I will be turning it in as soon as I receive it. Although this time I'll receive it in the mail instead of via print-out, I won't wait to turn it in. It's going on my calendar, in my planner, and on my phone alarms as a top priority.

If you're voting by mail like millions of Americans this year, don't wait to mail your ballot.

Carefully read all directions, and make sure to sign it where instructed. Most of all, check your local post office's pickup times–experts now suggest mailing your ballot by October 20 to compensate for any delays. By following these simple steps (and keeping an eye on the clock!) your early postmarked ballot will be on its way, no problem.