How to Train AI on Your Brand Voice
Generic AI output sounds like everyone else. Here is how to build a brand voice document that makes AI write like you - specific, consistent, and unmistakably yours.
The reason most AI-generated content sounds the same is because most people give the same instructions: "Write a blog post about marketing."
The AI has no idea who you are, how you speak, what words you use, or what makes your perspective different. So it gives you the average of everything it knows. Average content for an average brand. Nobody wants that.
Here is how to fix it.
Step 1: Document your voice attributes
Before you touch an AI tool, you need to define your voice in writing. Most brands have never done this. They know how they sound intuitively but have never written it down.
Answer these questions:
What is your tone? Blunt? Warm? Academic? Casual? Authoritative? Playful? Pick 3-5 adjectives that describe how you communicate.
What is your perspective? Do you speak from experience? From research? From a contrarian angle? From empathy? Your perspective is what makes your content uniquely yours.
Who do you sound like? Name 2-3 people or brands whose communication style is similar to yours (and 2-3 that you do not sound like). This gives the AI reference points.
For my personal brand, the voice attributes are: blunt, earned, competitive, raw, grounded, in your corner. I sound like a mate who has built and broken businesses. I do not sound like a LinkedIn thought leader or a corporate marketing team.
Step 2: Create a banned language list
This is the most underrated step. Telling AI what not to say is as important as telling it what to say.
Every brand has words and phrases that do not fit. Generic corporate language, industry cliches, and phrases that every other brand uses.
My banned list includes: synergy, leverage (as verb), unlock, level up, game-changer, disrupt, innovative, cutting-edge, empower, thought leader, scalable solution, next-level, journey, elevate.
If any of these words appear in AI output, it immediately breaks the voice. The banned list acts as a filter that catches generic language before it reaches your audience.
Step 3: Provide examples
AI learns patterns from examples. The more examples of your actual writing you provide, the better the output matches your voice.
What to include:
- 5-10 of your best-performing pieces of content (full text)
- 3-5 email newsletters you have sent
- Social media posts that got high engagement
- Any written communication that represents your voice at its best
Feed these to the AI with instructions like: "Here are 10 examples of my writing. Study the tone, sentence structure, word choice, and rhythm. All future content should match this style."
Step 4: Define your formatting rules
Voice is not just what you say - it is how it looks on the page.
- Do you use emojis? (I do not. Ever.)
- Do you use exclamation marks? (I do not. The words carry the energy.)
- Do you use hashtags? (No.)
- Do you use short paragraphs or long ones?
- Do you use headers and bullet points, or flowing prose?
- What punctuation style do you prefer? (I use normal dashes, never em dashes.)
These details might seem small, but they are the difference between content that feels like you and content that feels like a template.
Step 5: Build your system prompt
Combine everything from steps 1-4 into a single document - your brand voice system prompt. This gets fed to the AI at the start of every conversation.
The structure:
- Voice attributes (3-5 adjectives with explanations)
- Sounds like / does not sound like
- Banned language list
- Formatting rules
- Key statistics and proof points to reference
- 3-5 example pieces of content
Save this document permanently. Use it every time you work with AI on content. Update it when your voice evolves.
Step 6: Iterate based on output
The first outputs will not be perfect. That is expected. The iteration process is:
- Generate content with your voice document
- Read the output critically - what sounds like you and what does not?
- Give feedback to the AI: "This paragraph sounds too formal. I would say it more directly, like this..."
- Refine the voice document based on patterns you notice
- Repeat until the output consistently matches your voice
After 10-15 iterations, the AI output should be 80-90% aligned with your voice. The final 10-20% always needs a human editing pass - that is the layer of personal experience, specific stories, and raw honesty that AI cannot replicate.
The result
A properly trained AI becomes a writing accelerator, not a writing replacement. It handles the structure, the research, and the first draft. You add the personality, the specificity, and the human touch.
At Ignis, every client gets a custom voice document built during onboarding. It is the foundation that allows us to produce content at scale without losing the authenticity that makes it work. Our average client generates $3M+ per year - and the content that drives those results sounds like them, not like a generic AI.
Your voice is your competitive advantage. Train the AI to amplify it, not replace it.

David Eid
Marketing Strategist · Founder of Ignis
Marketing strategist based in Sydney, Australia. Founder of Ignis - premium marketing that scales businesses. Our average client generates $3M+/year and 1M+ views/month.
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