How to Get AI to Write in Your Voice

"Write it in a professional but friendly tone." Everyone has typed this. It does almost nothing, and it is obvious why once you look at it: "professional but friendly" describes several million writers. You have told the model which enormous bucket to draw from, not which voice to use.

Voice is not an adjective. It is a set of habits.

Start from what you have already written

You do not need to describe your voice. You need to show it.

Find three things you wrote yourself and were happy with. An email that got a good reply. A page you did not rewrite six times. A post that sounded like you. They do not need to be long, and they should not be things you laboured over — laboured writing is nobody's natural voice.

Ask for the patterns, not the vibe

Give the model those three pieces and ask it to work out how you write. Specifically:

• Sentence length and rhythm. Do you run long and build, or clip?
• Vocabulary you reach for — and, more revealing, words you clearly avoid.
• Formality, on a scale, with evidence from the text.
• How you open, and how you close.
• Your relationship to the reader. Peer? Teacher? Guide? Sceptic?

Then ask for two lists: five phrases that sound like you, and five that would sound wrong coming from you. The second list does more work than the first, because it is the one a model will otherwise violate constantly.

Turn it into one reusable paragraph

The output is only useful if you actually use it. Ask for it condensed into a single paragraph you can paste at the top of any prompt.

That paragraph is the asset. Keep it somewhere you can find it. Every writing prompt from now on starts with it.

Test it on something you can judge

Do not test a voice guide on new work — you have nothing to compare against. Test it by asking for something you have already written, and see how close it gets.

If it is off, the fix is usually in the "words I avoid" list. Add the specific thing that grated.

Voice is not the same as knowing things

A voice guide makes AI sound like you. It does not make it know what you know. Those are separate problems, and conflating them is why people conclude the whole exercise failed.

If the output sounds right but says nothing, the brief was thin, not the voice guide. Add the facts, the client, the number, the objection you actually get.

Keep it current

Voices drift, usually for the better. Redo this once or twice a year with recent writing, and you will notice the guide changing — which is a good sign, and worth keeping.