Probably the most oft quoted piece of advice is “write what you know.” I’d revise that to say “write what interests you.” You don’t need to know a great deal about a subject at the outset—I wrote a novel set partly in a Federal Reserve Bank and had never set foot in one—but interest in the subject is a way of signaling to oneself that you want to learn about it, and I think the curiosity behind learning and writing are not dissimilar. Thus, as far as subject matter goes, I could refine my answer to say “write about what you want to learn about.”
As for the practice itself, writing prose takes time. Keeping a regular schedule is vital, in my experience. There is so much failure built into writing—so many drafts of things you’ll never end up using or will use only a sentence of—that you have to be willing to spend a good deal of time working even if there is no satisfying ratio between the time spent and the finished pages won. So I would be determined, I would turn off the internet, turn off your phone, and write however many hours a day you can manage. We live in a wildly distracted age. In order to hear the voices inside myself that want expression, I find I have to try to quiet or even silence the louder more common ones of everyday modern life.
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