There are two primary methods for holding your hook: nearly vertical (the traditional method) and nearly horizontal (the contemporary method).
From there, you can hold your hook in basically any manner that feels comfortable to you: like an ice cream scoop, a pencil, a needle, or whatever else you can think of. Granted, if an unusual position suits you, you might confuse your teacher, and you will have to learn more of how the yarn is supposed to move rather than where precisely the hook should be when; but for your eventual ease and speed of crocheting, it will be worth it.