In larger companies the person who does this job, that is designs the "look" the company will have, designs the ad campaign and hires photographers -- this person has the job title of "Art Director" So you are asking really asking "How do I learn to become my own Art Director?". First off it helps a lot if you can draw, at least stick figures, know the basics of composition and color and so on. I think most have some formal art education. wikipedia has an intro and some links
http://en.wikipedia.org/wiki/Art_director Also google "Art Director"
Possibly, you want to contract with an art director and let him deal with the photographers. What he might do is make a stack of sketches and hand them to a commercial photographer to shoot s/he'l also write up instructions for color and composition and so on.