How to Create a Brand Voice Guide Your Team (and AI) Can Actually Use

A useful brand voice guide is short, specific and full of examples. It tells anyone writing for your business, whether that is a new hire, a freelancer or an AI tool, how you sound, what you never say, and what good looks like. Most voice guides fail because they list adjectives like “friendly, professional, innovative” that every business claims and nobody can apply.

The test of a voice guide is simple: could two different writers use it and produce copy that sounds like it came from the same company?

Why brand voice matters more now

When most content was written by one or two people, voice stayed fairly consistent by default. Now businesses publish across websites, emails, social posts, ads and proposals, often with several writers and AI tools involved. Without clear guidance, the result is copy that sounds generic in some places and inconsistent in others.

A consistent voice makes a business easier to recognise and trust. It also makes writing faster, because people spend less time guessing how something should sound.

Step 1: Start from your customers, not your adjectives

Your voice should suit the people you are talking to. A law firm advising small businesses, a fitness studio and a cybersecurity consultancy might all call themselves “approachable”, but they mean very different things.

Look at who your customers are, what situation they are in when they find you, and how they talk. Customer calls, reviews and emails are the best source. Our guide to voice of customer research explains how to gather this.

Step 2: Define three or four voice traits with boundaries

Adjectives alone are useless. Each trait needs a boundary that says what it means and what it does not. For example:

• Direct, not blunt. We say what we think and give clear recommendations, but we explain our reasoning and stay respectful.
• Expert, not academic. We show we know the subject through specifics, not jargon. If a client would not use a term, we explain it or avoid it.
• Warm, not casual. We are friendly and human, but we do not use slang or forced jokes.

The “not” side is what makes a trait usable, because it shows where the line is.

Step 3: Show examples of good and bad

Examples teach faster than descriptions. For each trait, include a short before-and-after:

Not like this: “We leverage cutting-edge methodologies to deliver best-in-class outcomes.”

Like this: “We look at where your enquiries are coming from, fix what is broken, and show you what changed.”

Include examples from the formats you use most: a website paragraph, an email opening, a social post and a response to a complaint. Tone can flex by context while the voice stays the same. A reply to an unhappy customer should be calmer and more careful than a social post, but still recognisably you.

Step 4: Add practical rules

This is where a voice guide becomes something people can follow without interpretation:

• Words and phrases you prefer, and ones you never use.
• Spelling conventions, such as UK or US English.
• How you refer to customers: clients, customers, patients, members.
• Formatting habits, such as sentence case headings, or whether you use exclamation marks.
• Claims you can and cannot make, especially in regulated industries.

Step 5: Make it usable for AI tools

AI tools follow instructions literally and default to generic patterns when instructions are vague. A voice guide that works for AI includes:

• A short description of the audience and their situation.
• The voice traits with boundaries.
• Two or three examples of on-brand copy for the model to imitate.
• An explicit list of phrases and patterns to avoid, including common AI habits like “in today’s fast-paced world”.

Save this as a reusable block you paste into prompts or into the custom instructions of the tool your team uses. Our article on AI copywriting prompts covers how to combine it with a strong brief, and our guide to editing AI copy covers the final human pass.

Keep it short enough to be read

A forty-page brand book is rarely opened. Aim for something that fits on two or three pages: who you are talking to, the traits, examples, rules. Link to a longer document if you need one, but make the core easy to scan.

Roll it out and keep it alive

Share the guide with everyone who writes for the business, including agencies and freelancers. Review new content against it for the first few weeks. Update it when you notice recurring problems or when the business changes direction. A voice guide is a working document, not a one-off brand exercise.

Want a voice that sounds like you everywhere?

We help businesses define a clear voice grounded in how their customers think and talk, then apply it across website copy, campaigns and AI-assisted content. See our AI Conversion Copywriting service or get in touch to talk about making your copy consistent and recognisably yours.