🧪 The Only Prompt Formula A Beginner Needs

Here’s a trap I watch people fall into every single week: they decide to “get good at AI”, so they start collecting prompts. Fifty prompts. Two hundred prompts. A bookmarked mega-list called something like ULTIMATE PROMPT PACK. And then they use AI exactly the way they did before, because a recipe book you never cook from is just a heavy shelf.

You don’t need a library. You need one formula and one habit. The formula covers roughly 90% of everything you’ll ever ask an AI, and the habit covers the other 10%. This guide is the whole thing, properly, with worked examples - because once this clicks, you can throw away every prompt list you’ve ever saved (including mine, and I say that as someone who’s taught this to rooms full of nervous beginners).

The Three-Line Brief

Think about how you’d brief a good tradesperson. You wouldn’t say “help me with my kitchen”. You’d say what’s going on, what you want done, and how you want it left. That’s the whole formula. I call it the Three-Line Brief: the scene, the job, the shape.

Line 1: The scene

What it is: one or two sentences on what’s going on and who’s involved - the context a helpful stranger would need before their advice could possibly fit you.

How to do it: say who you are in this situation (“I run a small café”, “I’m applying for office jobs after ten years in retail”) and what’s actually happening, including the awkward bit (“takings are down since the roadworks started”, “I’ve got a gap year I don’t know how to explain”).

The bit everyone gets wrong: leaving out the awkward detail because it feels embarrassing to type. The detail you’re tempted to hide is nearly always the one that changes the answer. Claude isn’t judging you… it literally cannot judge you. Put the roadworks in.

Line 2: The job

What it is: one proper verb and one clear thing. Draft, list, compare, rewrite, plan, explain, shorten.

How to do it: finish the sentence “I need you to…” with something you could tick off. “Draft a sign for the counter.” “List questions to ask at the viewing.” “Rewrite this so it sounds less annoyed.”

The bit everyone gets wrong: “help me with” is not a job. Neither is “any thoughts on”. Vague verbs get you a polite essay about your topic instead of a thing you can use. If you can’t name the verb, that’s useful information - it usually means the real first job is “help me work out what I’m actually asking for”, which is a perfectly good brief in itself.

Line 3: The shape

What it is: what the answer should look like when it lands - length, tone, format.

How to do it: “Under 100 words.” “A table.” “A bullet list I can read on my phone.” “Warm but no exclamation marks.”

The bit everyone gets wrong: skipping this line entirely, then being annoyed at the result. If you don’t choose a shape, you get the default shape, and the default shape is Long And Slightly Formal. Nobody wants Long And Slightly Formal. The shape line is one comma’s worth of effort and it’s where most of the “wow, that’s exactly what I wanted” feeling comes from.

The template

Here’s the whole formula as a fill-in, plus one bonus line that quietly does more work than the other three put together.

Nick this one, fill in the blanks:

The scene: I'm [who you are in this situation] and [what's going on, including the awkward bit].
The job: I need you to [one proper verb + one clear thing].
The shape: Make it [length], sounding [tone], formatted as [a message / a list / a table / a plan].
If you need anything from me to do this well, ask before you start.

That last line turns Claude from a machine that guesses into an assistant that checks. Keep it in everything.

Three before-and-afters

Watch the formula transform real asks. Same people, same problems, wildly different results.

The café owner. Weak ask: “write a social media post for my café” Three-Line Brief: “The scene: I run a small café and takings are down 20% since roadworks closed half our street - regulars think we’re hard to get to, but we’re open and there’s parking round the back. The job: draft a cheerful post telling people exactly how to reach us. The shape: under 80 words, sounds like a human not a marketing team, ends with the back-lane directions.” The weak ask gets a generic post about “cosy vibes and great coffee”. The brief gets a post that solves the actual problem.

The job hunter. Weak ask: “improve my CV” Three-Line Brief: “The scene: I’ve spent ten years in retail, two as an assistant manager, and I’m applying for office admin jobs - I’m worried my experience sounds ‘shop-floor’ when actually I ran rotas, cash, complaints and stock systems. The job: rewrite my CV’s profile and my last job description so the transferable skills lead. The shape: keep it to the same length as what I paste, no buzzwords I’d cringe reading aloud.” One gets vague polish. The other gets a translation of retail into office language, which is what was needed all along.

The parent. Weak ask: “plan my daughter’s birthday party” Three-Line Brief: “The scene: my daughter turns seven next month, we’ve got a budget of about £150, a small garden, twelve kids coming, and one of them has a serious nut allergy. The job: plan the party - food, three or four garden games, and a rough running order for two hours. The shape: a simple plan I can print, with a shopping list at the end.” The first gets Pinterest fluff. The second gets a plan you could actually run on the day, with the allergy handled in the food list rather than remembered in a panic at the bakery.

Notice none of the strong versions is clever. They’re just… complete. That’s the whole trick.

The habit: haggle

Now the other 10%, and it matters just as much: the first answer is a first draft, not a verdict. I call it haggling. Even a perfect brief gets you 80% of the way there, and the last 20% is three quick nudges: “shorter”. “Warmer.” “The middle bit’s great, lose the rest.” “You’ve made me sound like a solicitor, try again.”

Each nudge costs five seconds. People who seem brilliant at AI are not writing better first prompts than you - they’re just comfortable saying “not quite, again” without feeling like they’ve failed. The first answer is the start of a conversation, not the end of one.

Straight talk time

The formula can’t invent facts you didn’t give it - a brilliant brief about your café still needs you to mention the roadworks. It can’t pick your priorities for you: “make it good” isn’t a shape, and you’ll still need to decide whether warm beats brief when they conflict. And no formula stops AI occasionally getting facts confidently wrong, so anything important still gets a sense-check from you.

The one move

Add the bonus line - “if you need anything from me to do this well, ask before you start” - to your very next prompt, even a lazy one. Watching Claude ask you three sharp questions teaches you more about good briefs than any guide can, including this one.

Once the formula feels natural, go window-shopping for jobs to use it on: The 10 Prompts That Do Your Admin is a good rack to browse.