First off, welcome to the herd DusnRain.
Second, you can dress up for the event. However (and correct me if i'm wrong) but there's no weapons or masks allowed.
Thirdly, i would get in contact with the staff for volunteering for the con. You can do so here: events@everfreenw.com
Fourthly, a thing you can do is help out with the forums, and if possible, attend the public meetings.
Fifthly, there's not going to be a Sponsor badge for the event. We feel that we want to have everypony be on equal footing. That way, there's nopony left out or feel like they can't interact with certain ponies.
Sixthly, have a great day