There's a great interview with Francis Ford Coppola on the99percent. It's filled with brilliant nuggests of genius from a man that knows a thing or two about creativity. I particularly liked this one:
I remember in “The Conversation,” they brought all these coats to me, and they said: Do you want him to look like a detective, Humphrey Bogart? Do you want him to look like a blah blah blah. I didn’t know, and said the theme is ‘privacy’ and chose the plastic coat you could see through. So knowing the theme helps you make a decision when you’re not sure which way to go.