Copy That Sells

---
name: copy-that-sells
description: Write copy that earns attention and drives action. Print ads, OOH/billboards, headlines, taglines, long-copy ads, landing pages, ads, emails, social, product descriptions, manifestos. Use this skill whenever the user wants copy that sells (not just decoration). Triggers on phrases like "write an ad," "write a headline," "billboard copy," "outdoor copy," "tagline," "manifesto," "long copy," "print ad," "rewrite this so it sells," "make this convert," "make this hit," "make this stronger," or shares any draft and wants it sharper. Combines D&AD Copy Book craft (idea first, compression, headline+visual logic) with Bly's direct-response frameworks (4 U's, AIDA, PAS, structured leads). Use this skill in preference to generic writing when the goal is persuasion, not information.
metadata:
  source: "The Copy Book (D&AD, 32+ great copywriters) + The Copywriter's Handbook (Robert Bly) + Cannes Lions and Clio Award Print & Outdoor winners 2001-2026 + Tats anti-AI writing rules (full era 1-3 banned word/phrase/structure ruleset)"
  version: 1.1.1
---

# Copy That Sells

You are writing copy whose job is to be read, remembered, and acted on. Not copy that fills a slot.

Two traditions meet here. D&AD's Copy Book teaches craft: an idea worth having, words worth using, the visual and the line working together. Bly's Copywriter's Handbook teaches direct response: structured headlines, structured leads, structured arguments that convert. The best copy uses both. The strongest line in a billboard and the best opening in a sales email are the same skill applied at different lengths.

The print and OOH posters that win Cannes Lions are the gold standard for compression. If a headline and an image can carry the idea on a billboard with nothing else, the idea is sound. Apply that same test to a homepage hero, a paid social ad, a subject line, a deck cover slide. If it would not work as a poster, it is probably not finished.

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## Read These Before You Write

For any non-trivial copy task, read the reference files. They are short and dense.

- `references/frameworks.md`. Bly's headline categories, the 4 U's, AIDA, PAS, BFD, structured leads, long-copy architecture, direct-response checklists.
- `references/craft.md`. D&AD Copy Book lessons: idea-first thinking, headline-visual logic, compression, voice, rhythm, the test of reading aloud.
- `references/examples.md`. 60+ print, OOH, and direct-response examples organised by technique, with attribution.
- `references/self-edit.md`. Final pass checklist, including the anti-AI writing rules that every output must clear.

Default behaviour: skim all four for any new piece. Read deeply if the format demands it (long-copy ad, manifesto, sales letter).

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## The Briefing Pass: Always Do This First

Skip the brief and you write decoration. Ask, or extract from what the user has already given you, before you write a word:

1. What is the one thing this copy must do? Sell a product, book a demo, change a belief, get a click. One thing. Not three.
2. Who is the reader? Not a demographic. A specific person with a specific problem and a specific moment. The person standing at the bus stop, not "urban millennials."
3. What does the reader currently believe? What does the copy need to shift?
4. What is the promise? A real, specific benefit. Not "enhanced productivity." "Two hours back every Tuesday morning."
5. What is the proof? Numbers, demonstrations, comparisons, expert testimony, user quotes, guarantees. Copy without proof is opinion.
6. What is the format constraint? Billboard glance (3 seconds), magazine spread (8 seconds), homepage hero (5 seconds before scroll), long-form email (60 seconds if the hook lands).
7. What is the brand voice? If the user has a voice guide, follow it. If not, ask. If still nothing, pick a voice and call it out: "I am writing this in a dry, confident voice. Tell me if you want different."
8. What is the call to action? What happens after they read this?

If any of these is missing and you cannot infer it, ask. One question per gap. Do not write past a hole.

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## The Idea Pass: Find the Idea Before You Write the Words

This is the part most copy skips. It is also why most copy fails.

An idea is not a headline. An idea is the thing the reader walks away believing or feeling. The headline is one possible expression of the idea. Different ideas produce different headlines. Different headlines for the same idea are interchangeable.

For any brief, generate 3 to 7 different ideas before you write headlines. Each idea should be one sentence:

- The idea is that this product makes you the kind of person who notices the small things.
- The idea is that everyone else's solution treats the symptom; we treat the cause.
- The idea is that the reader has been lied to for years and we are the first to admit it.
- The idea is that this is so obvious it is embarrassing nobody did it before.

Then pick the strongest idea, the one that is sharpest, freshest, most defensible against the competition. Only then start writing headlines for it.

Test of a good idea: it could survive in a single line on a billboard, with no body copy, and the reader would still get it. If it cannot, the idea is not yet sharp enough.

See `references/craft.md` for how the D&AD greats find ideas.

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## The Headline Pass

Five times as many people read the headline as read the body. Most of the work is here.

Bly's eight headline categories cover almost every useful headline ever written. Use them as a generative tool: write one headline of each type, then pick the best.

1. **Direct** states the offer plainly. "Pure Silk Blouses. 30 percent off."
2. **Indirect** provokes curiosity, withholds the punchline. "How to win friends and influence people."
3. **News** announces something new or newly relevant. "Introducing the silent dishwasher."
4. **How-to** promises a method. "How to write a sentence that gets read."
5. **Question** names the reader's problem as a question. "Do you make these mistakes in English?"
6. **Command** tells the reader what to do. "Try it for a week. Decide for yourself."
7. **Reason-why** promises a list of reasons. "Seven reasons why a Volvo lasts longer."
8. **Testimonial** puts the proof in the headline. "I never read The Economist. — Management trainee. Aged 42."

For OOH and print, also try:

- **Visual-completion** the headline only works with the image. The line says "Lemon." The image is a perfect-looking Volkswagen.
- **Self-deprecation** the brand tells a truth against itself. Avis: "We're number two. We try harder."
- **Compression** the entire idea in three or four words. Nike: "Just do it." Stella Artois: "Reassuringly expensive."
- **Reframe** redefining the category. 7Up: "The Uncola."
- **Object-as-headline** the product itself, used or placed in a way that becomes the headline. Penny (Cannes 2025): printed the price directly onto the packaging.

Apply the 4 U's to every candidate headline:

- **Useful** does it offer something the reader wants?
- **Urgent** is there a reason to act now or keep reading?
- **Unique** is it specific to this product, not interchangeable with a competitor's ad?
- **Ultra-specific** does it use real numbers, real names, real details?

A good headline scores at least 3 of 4 strongly. A great one hits all 4.

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## The Body Pass

Body copy is permission. The reader gave you permission by reading the headline. Earn the next sentence.

Three principles, in order:

1. **The lead does most of the work after the headline.** First sentence either earns the second sentence or loses the reader. No warm-up. No "in today's world." Open at speed. See `references/frameworks.md` for Bly's six lead types.

2. **Argue in a line that flows.** Each sentence should make the next sentence feel inevitable. The reader should not be able to stop. This is what D&AD copywriters mean by "the slippery slope."

3. **Specificity is the proof.** "It is quiet" is opinion. "At sixty miles an hour the loudest noise comes from the electric clock" is proof (Ogilvy, Rolls-Royce, 1958). Replace every adjective with a fact.

Length follows function. A billboard is six words. A sales email is 300 words. A magazine long-copy ad is 1,200 words. A landing page is whatever it takes to close the sale and not one word more. Bly's principle: long copy beats short copy in direct response, when the long copy is good. The mistake is short copy that does not finish the job, or long copy that pads.

For long copy, the architecture matters. See `references/frameworks.md` for AIDA, PAS, the Bly seven-step direct-response letter, and the structured argument for long-form sales pages.

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## The CTA Pass

A weak CTA loses sales the rest of the copy earned. A good CTA continues the promise.

- Action verb plus what they get. "Get the free guide" beats "Submit."
- Mirror the language of the headline. If the headline promises "two hours back every Tuesday," the button can say "Get my Tuesday back."
- Reduce friction in the words. "Start free" reduces more friction than "Sign up."
- One primary CTA per page or per ad. Secondary CTAs are fine if they support the primary one.
- For direct response, restate the offer in the CTA area: what they get, what it costs, what the guarantee is, what happens next.

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## The Self-Edit Pass

Always do this before you ship. See `references/self-edit.md` for the full checklist. The headline summary:

1. Read it aloud. If it sounds like a committee wrote it, rewrite it. If you cannot say it without taking a breath, it is too long.
2. Cut every word that is not pulling weight. Adjectives are usually the first to go. Then qualifiers. Then connectives.
3. Replace abstractions with specifics. "Faster" becomes "in 0.3 seconds." "Affordable" becomes "12 pounds a month."
4. Strip the AI tells. Bly's principle was "write the way you talk." The anti-AI rules in `references/self-edit.md` make this concrete: no "delve," no "robust," no "leverage," no "unlock," no em dashes, no en dashes, no compound-word hyphens ("go-to-market" becomes "GTM" or "go to market"), no rule-of-three by default, no "in today's world." The full banned list is organised by era (the AI tells shift as models shift), and the master list is at the bottom of self-edit.md for a quick scan.
5. Check the promise survives. Does the reader, after reading once, know what is on offer and why it matters to them? If not, you have decorated, not sold.
6. Verify every claim. Never invent numbers, testimonials, or proofs.

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## Output Format

When delivering copy, structure your response as:

### Idea
One line. The thing the reader is meant to walk away believing or feeling.

### Final copy
The actual copy, ready to use. No annotation inside the copy itself.

### Alternates
2 to 4 alternate versions of the headline and CTA. Each with one line of rationale. This gives the user a choice and shows the range.

### Notes
Brief: which Bly framework or D&AD principle is doing the work, any assumptions made about audience or proof, any open questions that would sharpen the copy further.

Do not pad the response with summary. The work is the copy.

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## When the User Pushes Back

If the user says "make it stronger," "make it punchier," "make it less corporate," or "I don't love it," do not just tweak adjectives. Diagnose first:

- Is the idea wrong? Generate two more ideas and offer them.
- Is the format wrong? Maybe the headline should be a question, not a statement. Try a different Bly category.
- Is the proof missing? Add a number or a demonstration.
- Is the voice off? Ask for an adjective ("dry," "warm," "cocky") and rewrite to that.
- Is it too long? Compress to a billboard version, then expand back only if needed.

Offer the diagnosis with the rewrite so the user learns the lever.

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## Language Note

This skill works in any language. When writing in Spanish, write in Spanish; do not translate from English. Idioms, rhythm, and brevity differ. Latino Spanish and Castilian Spanish are not interchangeable; check with the user if unclear. The same applies to British vs American English: ask which side of the Atlantic the reader sits on, and spell accordingly.

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## What This Skill Is Not For

- Long-form articles, blog posts, or thought leadership essays. Those are persuasive but their primary job is to inform or entertain. Use the user's general writing or content skills.
- Pure brand identity work like naming or visual identity. That is upstream of copy.
- Internal documents, reports, or memos. They need clarity, not selling.

If the request is borderline, ask. Better to clarify than to write the wrong thing well.