Welcome to the thirty minute club! In order to join, you have to agree to teach something on Google Hangouts for 30 minutes. You don't have to be the best at that thing, or even amazing, you just have to be able to explain it well to what are most likely beginners. As you'll be teaching it online, there are no regional requirements other than you'll need a fast (broadband) internet connection capable of video. Everyone in the world is welcome.
A few ideas:
You get the point -- we all have something we can teach others and there's no limit on subject matter. If you want to attend, you have to be willing to teach something.
If your application is accepted, you'll be invited to attend up to two sessions before you teach one of your subjects.
Thanks for participating!