How an editorial style guide works
A style guide is a set of decisions, written down once so nobody has to make them again. It settles which spelling you use, how headings and job titles are capitalised, how dates and currencies are written, whether contractions are allowed, what the company is called on second mention, and which words you use for the things you sell.
Most of it is terminology. Deciding that you always write “Google Business Profile” rather than three different versions of the name, or that one service has a single name across the site, the ads and the invoices, removes far more confusion than any rule about commas.
Voice belongs in it too, but only in a usable form. “Friendly and professional” tells a new writer nothing. A pair of example sentences — one you would publish, one you would not — tells them almost everything, and that is the point where a style guide and a tone of voice document meet.
Why an editorial style guide matters
The moment more than one person writes for the business — an employee, a freelancer, an agency, an AI draft someone edits — the site starts to read like several different companies. Readers rarely name the problem, but inconsistency quietly costs trust, and it costs most on the pages where someone is deciding whether to hand over money.
It also saves time on every piece. Editing stops being an argument about preferences and becomes a check against agreed rules, and a new writer’s first draft arrives closer to publishable. On a bilingual site, where the same term can be written several ways, the guide does even more work.
Common mistakes with editorial style guides
Writing one nobody can use is the classic failure: a long document that anticipates every eventuality, is read once and never opened again. A short guide answering the questions people actually ask beats a thorough one that sits unread in a folder.
Leaving out the practical fields is the second. Headings, page titles, meta descriptions, button labels, form labels and alt text are where inconsistency is most visible to a visitor, and they are exactly what a guide written by a writer tends to omit.
The third is never updating it. A guide that still names a service you renamed last year teaches new writers the wrong thing, and once people catch it out they stop consulting it at all.
How to act on it
Start from what already exists rather than from a blank page. Read a handful of your best pages, note the decisions they are already making, and write those down. You will have something usable in an afternoon, and it will match how the business already sounds instead of describing a company you wish you were.
Keep it to a page or two, order it so a question can be answered in seconds, and lead with a word list: the terms you use, the terms you avoid, and the ones people keep getting wrong. Give it to everyone who writes anything, including whoever edits AI drafts, and add a line each time the same correction is made twice. Maintained that way it underpins consistent content marketing and makes every content brief shorter, because the standing rules no longer need repeating.