“Being creative is a full-time job with its own daily patterns. That's why writers, for example, like to establish routines for themselves.
The most productive
ones get started early in the morning, when the world is quiet, the phones aren't ringing, and their minds are rested, alert, and not yet polluted by other people's words.
“They might set a goal for themselves — write fifteen hundred words, or stay at their desk until noon — but the real secret is that they do this every day. In other words, they are disciplined. Over time, as the daily routines become second nature, discipline morphs into habit. […]
“Daily routines are transactional. Everything that happens in my day is a transaction between the external world and my internal world.
“Everything is raw material. Everything is relevant. Everything is usable. Everything feeds into my creativity.
“But without proper preparation, I cannot see it, retain it, and use it. Without the time and effort invested in getting ready to create, you can be hit by the thunderbolt and it'll just leave you stunned.”
From The Creative Habit by choeorgrapher Twyla Tharp. And there's a good discussion of the issues raised by this blog post and the book over on Flickr.