Here’s a great tip list from Brian Pohl, CEO Persistence Of Vision
“If you want to become a previs artist focus on:
1. Camera Animation and cinematic language.
2. Camera Angles, Composition, and Continuity.
3. Low Rez Poly modeling and digital sets.
4. Low Rez Poly characters and rigging.
5. Understanding storytelling.
6. Editing and timing.
7. Non Linear Animation.
8. Tricks and cheats for improving speed and setup.
9. Animation vs VFX pipeline structures.
10. Integration for technical previs.
11. A solid understanding of various camera lens, camera backs, and aspect ratios.

A previs artist is: A Director, a Director of Photography, an Animator, a Modeler, a Rigger, an Editor, a Storyteller, an FX artist, a MoCap engineer, and so on. If anything, to become a previs artist, you must be ready to don any of these hats at anytime. However…ultimately, you’ll have to decide if you wish to focus on conceptual previs or technical previs. Each focuses on different parts of the preproduction pipeline.”

if you want to read more about previz, try my other previz blog Brian is also running a previz course at Gnomon