Artists tend to imagine that there's this creative voice inside us that is trying to get out, to make itself heard. This is our creative mind, the source of our work. Conventional wisdom is that creative ideas come from some rich inner well... the subconscious, the right side of the brain...
But maybe ideas don't really come from anywhere - maybe they don't really exist until you do something to bring them into existence. Perhaps the feeling that they exist, and need only to be expressed, is an illusion. It just seems like they already exist, but they don't. The really great ideas seem to come from nowhere.
Our creative mind may in fact not be a SOURCE of anything other than opinions, desires, needs. Our creative mind may not create things, but rather hunger for something that doesn't yet exist - something it can get only by forcing you to create it.
There are lots of rules to follow when making good pictures. It's relatively easy to analyze a picture and see if its underlying design (or composition) is solid, and so on. But what gets that picture started? What are the rules for that? How do we go about that?
The truth is, the so-called "creative" process isn't really so much about creating as it is about getting started on something, anything, and then reacting - the starting point can be almost entirely random. The process is entirely reactive.
What's not random is the perception you have of that first scribble, that first line of text - how it affects you, what you pick up on, and choose to enhance and develop, like a Rorschach test that takes into account your entire life up to that point, your current mood, feelings and thoughts and even your intentions (even though your intentions may have had very little to do with the nature of that first mark).
So if you're sitting around dreaming of the day that great idea for a book, picture, song, whatever is going to pop into your head fully formed, in some kind of creative lightning strike, I suggest you instead pick up a pencil (iPad?) and get working.