Elmore Leonard, a great crime writer, with a terrific sense of humor has Ten Rules of Writing that you can find posted on the web. (Google his name and they should come up.) The one I like best as a mystery novel writer is: "Try to leave out the part that readers tend to skip." He says this is "perpetrating hooptedoodle".
Since I am a novel writer, I know novel formatting. Where does one get formatting requirements? From agent and publisher submission guidelines which are standard on publisher/agent web sites these days. If writing a novel to send out to an agent or editor for print publication the standard page format is: one inch margins all around, page number in header in the top right hand corner, title of book/last name in the header on the left, double space, courier or times new roman 12 pitch. In the "old days" before computers, this formatting allowed about 250 words per page which helped editors determine how many words the novel had. Caveat: always check submission guidelines for the publisher/agent you are targeting to make sure you have the formatting they are requesting.
I used to write in courier but now I write in TNR. When I have converted manuscripts I loose page count. I'm not sure why so it is now confusing when one talks about page or word count for a novel. Now I go by computer word count instead of multiplying 250 by the number of pages.
For digital publishing, again one has to go by what the publisher needs. Digital readers do not have pages. So when I submitted to BookBaby, I took out the pages, header information, put in Table of Contents by Chapter, About the Author, Title Page, and disclaimer page. The e-publisher links the Chapters in The Table of Contents to the Chapter in the book. They also required paragraph formatting and not Tabs for indenting paragraphs.
For poetry, short story, essays, etc. same advice applies. Check the submission guidelines for the agent, publisher or contest you want to submit to. Good luck!
Not everyone would agree with me on this one, but I think it is important for a serious writer to write with the idea of getting published. It makes us stretch, to go out on the limb, stick our necks out and all those other cliches. (Sometimes cliches are the best, aren't they?) With it goes having a daily (week day) practice of writing. Having a set time and a goal for the day. How many words or pages? You get the idea. If I'm writing for publication then I am formatting my work so that if I want to send it out to an agent or editor, it is ready to go. Digital publishing format is a little different. (See post on formatting.) If I'm writing to publish, I start thinking about my readers, the market I'm writing for. I start studying submission guidelines, peruse writer magazines to see who is seeking what, get out the book Writer's Market and look up publishers. Now one can write for writing sake, but then one's feet are not to the fire. One can just diddle around endlessly. No, I suggest writing to get published.
I'm a serious writer, meaning I have a regular daily writing habit, and I'm interested in sharing my work through publication. My favorite literary form is the novel. I write to entertain myself and my readers.