The main contest is on Saturday. That's when all the entries are shown to a large audience by category. The audience is given ballots with all the videos to vote for their favorite ones in each category. After the showing the judges count those votes (for days) and then on Tuesday they show the winning videos and present the awards at the AMV Award Ceremony where the winning creators go up on stage and accept their award (if they're at the con). At least that's how it wen't last year.
It's natural to be nervous but it's just like any other contest if you've been to a con before. Except for the massive audience, but that's one of the reasons it's so fun. So don't worry and have a good time and best of luck to ya! (Even tho we're still awaiting the finalist list ATM...

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