You don't need to be a great artist. Some sketching abilities are helpful, as the major will require you to take basic drawing classes such as Anatomy and color theory, among others. If you pay attention to the techniques used and practice a lot, you should be able to keep up. Draw during your free time. Drawing is one of those things that you could become better through studying your subject and practicing. But in some cases, you either have it or you don't.
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