For me, there is a strong connection between inspiration and a mug of strong, over-sugared coffee.
I'm torn about concepts like writing a short story in an hour or a novel in ninety days, though I decided to give the latter a whirl as sort of a self-experiment. A few years back, I would have categorically denied the usefulness of such approaches, but I'm beginning to wonder if I don't greatly underestimate the value of deadlines even, and perhaps especially, for creative writing.
I do quite a bit of technical writing in my job, and used to review games and software a couple decades ago for print magazines, and I can't quite deny that some of the better stuff I wrote was the immediate result of tight deadlines that could not be extended no matter how much I squirmed or whined.
The same may be true for creative writing. Writing drivel is probably more helpful than not writing while waiting for inspiration to hit. You may wait for a long time. Caffeine-induced muse aside, I find that once I actually get my uninspired butt up and start writing, even if it feels like wading through a swamp, eventually I reach a point where new ideas do come up more fluidly. Perhaps the brain is, in essence, just like a muscle.