For me, it is often *quiet*. Not five muntues if silence, of course, but being able to get to a place where your body and environment have 'quieted down' and you can get your mind to follow. I just read this week about how the brain behaves during those 'ah-ha!' moments, and for me, getting into the writing headspace is very similar. You have be be ready to let the mind 'drift' a bit, to drop the normal routine (for me, a scientist is emminently logical and methodical), and take that leap - be it intuition or creativity. It sounded to me like that can be learned/developed, and it really matches my personal experience.