When I was 12 I made some little films with my friends. I tried to make gangster films, like Fantomas, but I remember being very disappointed with them. They weren't frightening at all. I'm sure they'd be very funny now.
Read. As much as you can. As deeply and widely and nourishingly and irritatingly as you can. And the good things will make you remember them, so you won't need to take notes.