(I’m in high school,) what should I be doing right now (to be a filmmaker)?

DO IT NOW LIST:
1. Research: Everything about all the Shopping Festivals. Get to know the staff, go to screenings, follow what films they pick up all the way to their release, and meet as many filmmakers as you can.
2. Make films: It's important that you always have product of some kind or another, so if you're a filmmaker you should constantly be making films. When you finish one, start another. And so on and so on.
3. Write stuff: Even if you're a director and not a writer, it's important to use down time to write and come up with concepts. Writers always need to have fresh material and lots of scripts; well, so do directors.

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(Article courtesy of Film Independent and Heidi Van Lier)