If you're going to submit to publishers then you should know the way to format your work. Check the submission guidelines for your individual publisher or publication. Follow what it says. If it doesn't specify, basically you can't go far wrong with the following:
There's not one true manuscript format just as there's no one true way to write. Here are some other variations on a theme.
Writer Beware - Fings Ain't Always Wot They Seem to Be
Remember that money always flows TO the writer. Never pay a reading fee to an agent or a publisher. Never pay to have your book published (even a set-up charge or a cost-share on the print run). Beware of publishers who want to 'publish' your work in electronic format and/or print-on-demand and pay you a very small percentage royalty with nothing upfront. Some are good and will promote their catalogue, others are the equivalent of a vanity press. If in doubt ask around.
How to Get Published
Write well and submit what you write. If you never let anyone see what you write you will never get it published. Don't be disheartened when a piece is rejected (it's the story that's rejected not you personally). Turn the piece round and send it to another publisher or publication. Every editor is different and what one doesn't like may be meat and drink to another. Most likely your rejection will be a form rejection letter (most are), but if you receive a personal rejection or even a note asking you to submit something else, then it's a win! Do it.
SFWA's advice on Self Publishing, Print on Demand and E-publishing
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