Full choreography sketch for a song, conceived/written in the time it took to listen to the song straight through once (three and a half minutes). This is a testament to how far I've come: less than a year ago the same amount of choreography would have taken me a full week.
Choreography, I've found, is part inspiration, but also part experience. The more experience you have, the quicker the inspiration comes (and really, this is applicable to a lot of the arts - I see this in my writing as well). You discover what you like and where you like it. You develop a sense of where things should sit in the piece. You get a feel for the art form and you start to be able to tell innately what does or doesn't work, even if you can't explain why. No amount of book-learning can do that for you. (It kills me to say this, because I love learning through reading.)
That's why if you want to be an artist, you have to be dedicated. You have to put in the years of work before you get good. You can find quotes from artists in any discipline to the effect that you have to write a hundred songs before you begin to learn how to write a song; you have to paint or draw a hundred pictures before you really begin to understand how to draw or paint; you have to put in ten thousand hours of work before you can say you have begun to master something. Choreography is no different. I've fully choreographed 78 songs (and probably started and not-yet-completed that many again, plus I have about a dozen that I'm actively working to finish) and I'm only just starting to feel like it's coming naturally. This has been fully five years since I finished choreographing my first piece, and I was choreographing snippets of things in my head long before I ever finished that one.
That said, I would be remiss if I didn't note that I was taking ten hours of dance per week last calendar year, that I was practicing tap every day except Sundays through this past summer and again since January, that I've been watching a TON of tap dance on YouTube in my spare time, that I have a subscription to Operation: Tap's online lessons and those have been invaluable in jump-starting my practice sessions, that my tap teacher at the college this year pushed me hard (because I asked her to), that I've been clapping rhythms to almost literally every song I've heard in the past six months, playing with different patterns. A lot of groundwork has been laid in my foundational tap dance technique over the past year and that has gone a LONG way in allowing my choreographic voice freedom of expression.
The next step is to figure out what exactly it is that I want to express.