I just watched a TED talkby Elizabeth Gilbert, author of Eat, Pray, Love, about using some of the old ways to nurture creativity. She talks about how the Greeks and Romans would ascribe creativity to an outside source (a muse, daemon, or genius) - that instead of 'being' a genius, we all 'have' a genius. This concept would help to buffer the artist from internalizing things like anxiety about doing poorly or not finishing.
I was really moved by this talk because I tend to feel that much of my creativity does not come entirely from me, but is inspired by Spirit. I tend to feel overcome by words or music when writing chants, as if they are being given to me by the gods, or being drawn up from something inside me with a little outside help.