Read interviews from top people working in the Art Department in the movie industry today. Production Designers. Art Directors. Storyboard Artists. Costume Designers.
It’s not as easy as it looks on tv. The hours are beyond gruelling and at first the money is non existent. But keep at it. Be nice to everyone, cuz you never know where your next job is coming from and who that Production Assisant will be later (maybe your next Production Manager) and only work for free for a little bit. Then bill what you’re worth and if you are good at it, the money will come. Make sure you like your scripts and it’s easier to live with them 24/7 for months on end. Take advice from people who are successful in the department you want to be in, and learn to take criticisms well and not personally.