A reference document that establishes consistent rules for grammar, punctuation, formatting, and usage across a manuscript or publication.
A style guide is a set of standards that governs how language is used in a particular context. For fiction writers, this can mean a publisher's house style, an industry standard like the Chicago Manual of Style, or a personal style sheet you create for your own manuscript. It answers the questions that grammar alone doesn't settle: Do you use the Oxford comma? How do you format telepathic dialogue? Is it okay to start sentences with 'And'? A style guide turns those decisions into consistent rules instead of leaving them to chance.
Inconsistency is distracting. If you capitalize a made-up term in Chapter 3 but lowercase it in Chapter 12, readers notice - even if they can't articulate why something feels off. A style guide prevents those micro-inconsistencies from accumulating. It also saves you time during revision because instead of making the same decision fifty times, you make it once and refer back.
Create a one-page personal style sheet for your current manuscript. Include at least three formatting decisions (like how you handle internal thoughts or text messages), three spelling or capitalization choices specific to your story, and three grammar preferences (like Oxford comma usage or sentence fragments). Keep it somewhere you can reference while revising.