The Writer's Notebook

John Irving, the author of The Cider House Rules, reportedly said:

It doesn't really matter who said it, it's so obviously true: Before you can write anything, you have to notice something.

And it's advised to write down what you have noticed. 

Horne, Theroux, Boyt and Chaudhuri posted on The Guardian ‘Messy attics of the mind’: what’s inside a writer’s notebook?" (6 April 2018). In the post, they related the following about Henry James:

Jotting things down in a notebook is one way writers shape and discipline the unpredictable flow of ideas. For Henry James, in 1881, just after publishing The Portrait of a Lady, it was already a matter of regret that he had “lost too much by losing, or rather by not having acquired, the note-taking habit”. But he would make up for it over the next 30 years by filling innumerable pages with his records of story ideas, anecdotes from dinner parties and newspapers, things noticed on his travels. He developed personal rituals around the process of expressing his thoughts, through the pressure of pen on paper.

Thus, keep a cahier handy to jot down fiction that you may (creatively) turn into non-fiction. 

"Bob with Books"

 

Source: Nancy Holt Bob with Books: Roof of 799 Greenwich St., New York, 1971

Sleep Less | Write More

Mary Oliver, winner of the National Book Award and the Pulitzer Prize, reportedly advised:

If anybody has a job and starts at 9, there's no reason why they can't get up at 4:30 or five and write for a couple of hours, and give their employers their second-best effort of the day—which is what I did.

However, if you're like me, a night owl, I would recommend, after a twenty minute power nap, staying up a couple of hours after one's bedtime to write. 

Like Mary Oliver alluded to, it's difficult to find time to write if you work and sleep for a a combined 16 hours per day.