Knowing the estimated timeframes of each stage of the book publishing process is prudent. In business they say, time is money, and it should be accounted for, wisely.
Writing is a creative process that expands the concrete representations embodied in our thoughts. In book publishing, we say, “everyone has a story inside them,” but writing it depends on your idea. Every other detail in your story is there to feed and cushion the idea so that it serves its purpose to the reader. While there are many starting points in the journey of writing, you only need to figure out what works best for you.
With nonfiction work, you always have to get your facts rights. Many writers may not know the writing styles which they can employ when writing. Pick a writing style that best tells what you want to say and you can never go wrong with nonfiction. At times, the kind of work you want to write will indicate to you the angle to write from. But it all starts with penning down that idea, that thought, and your story will flow.