I often find during my creative process for design projects, munching a burger or a coke, or even driving in rush hour that I have gentle or even sometimes magnificent leaps of creative thought. As Stephen King once noted, a good writer can't tell you where an idea came from. Nor, can a most other creative people explain the creative process any better than a writer.
Some creative people call it intuition. It just feels right.
There are times when this is true; I have to say that it happens rarely in my business life (which is far too concerned with low-level nuts-and-bolts design at present), but it does in my theatre design.
What usually happens is that, as the director explains the play, I get a picture in my head of what I want to create for the publicity. I will then play around with this idea for hours, and will often come out with something completely different. Occasionally, an idea sticks and stays throughout.
One of these was when I was auditioning for a newly written play, and the writer/director was describing it. It was a simple idea, the play leaping out of the boundaries of the stage; the storyteller becoming involved in the tale that he was telling, taking control as the characters start to defy his memory. And for some reason, the image of a burning book came into my head. I played about for only a couple of hours, and came up with what remains one of my favourite bits of artwork.
The play was, obviously enough, The Last Chapter of Dreaming (yes, I did get a part) and it was written, interestingly, by this man. I enjoyed it.
Sometimes, though, a piece never quite comes right. I usually find that it is because of interference! I did a piece recently in which the director wanted to use a particular photograph. Because of the constraint of that photograph, the poster just didn't come out right and didn't satisfy me: I couldn't get a flash of inspiration for the composition because the photograph always... in the way. The end result was serviceable, but I just got embarrassed when people told me that they really liked it, because it just didn't feel right to me.