I want you to try picking out individual notes first, so all you're concentrating on is melody. If you're a lyricist who doesn't write any music, then your assignment is to write some free verse about each character, being careful not to duplicate anything that has already been said in the text or dialogue. Theme songs for movies should be all subtext, so let's assume the same is true for books. If you absolutely hate this story and can't bear to read another sentence, then go see my pal Slash at Super Crown, choose another book and do the assignment with it instead. The chances are good you'll go through several drafts before you're completely happy with your work.
Most professional songwriters think of the first draft as being the inspirational one.
Then the craftsperson in each of them takes over to do the refinements. My clients find that having this kind of specific homework gives them focus, instead of having to wait for inspiration before starting a new song. The first paperback printing was two years later, and now, seven years after that, it's a best-seller. This rarely happens in the book business. Just like a CD, you get a couple of weeks and boom - if you don't sell, you're quickly replaced with someone else's dream.