Brand voice

The upstream dependency for every writing skill. Draft before this exists and it comes back sounding like everyone else.

With existing samples

Collect ten to twenty real pieces the person considers representative — their best, not their most recent. Then extract, with evidence:

• Sentence rhythm — average length, and whether they vary it deliberately. Most distinctive voices are distinguished by rhythm before vocabulary.
• Vocabulary tells — the words they reach for and the register they avoid. Note both.
• Opening moves — how they start. Most writers have two or three habitual openings.
• Stance — do they assert, hedge, question, or provoke? Who do they assume the reader is?
• Humor and its absence — where it appears and where it never does.
• Formatting habits — paragraph length, list usage, emphasis.

Quote a real example for each. A voice guide with adjectives and no samples is unusable.