Ruth Bjorklund 
Costume Design in Theater [PDF ebook] 

If you have a love of history and clothing, there is a role for you in the theater. This book outlines the skills needed to be a costume designer, what must be done while the show is being rehearsed, and what the designer does during and after the performance. There is a chapter on how these experiences can translate to work in the real world, and there is a sidebar about someone who has made a career out of a love of clothes.