How to create viral content: the share sentence, the opening, and the five shapes that travel

Content gets passed on when it gives the sender something: a line they can repeat, a fact that makes them look informed, a demonstration that settles an argument, or a feeling strong enough to want company. So the way to create viral content is to decide which of those you are handing over, write the sentence the sender would use, and then build the piece backwards from that sentence. Everything else, the hook, the format, the length, the caption, is production detail in service of it.

This page is about making the content itself: the share sentence, the opening seconds, the five shapes that travel, how to make a piece native to one platform, and the numbers that tell you whether it worked. The design of the loop around it, meaning how one share turns into the next, is a separate job and it is covered in our guide to viral marketing and the four loop types.

Write the share sentence first

Before you film or write anything, put down the message somebody would type when they send it on. Not your caption. Their words. "Watch this guy fix a cracked phone screen with a hair dryer." "This is why your dentist keeps asking about your gums." "Forward this to anyone still paying for parking at the airport."

If you cannot write that sentence, there is nothing to send. If the sentence needs two clauses, the piece has two ideas and one of them is costing you the share. The sentence also tells you the format: a line that begins "watch" needs video, a line that begins "this is why" needs an explanation, and a line that begins "forward this to" needs a useful artefact somebody can act on.

The opening, which is the whole bet

A viewer decides in the first second or two, so the opening carries the specific promise rather than the setup. Five openings that do the work:

• Show the finished thing first. The restored chair, the cleared drain, the before and after, then go back to the beginning.
• State the payoff as a claim. "You are allowed to claim this and almost nobody does." The viewer stays to find out whether it is true.
• Open on the contradiction. Something that should not work, visibly working.
• Name the person. "If you rent a flat with a gas meter, this one is yours." Exclusion makes the people inside it pay attention.
• Start mid action. No introduction, no logo, no "hi everyone". The hands are already moving.

Then keep the first ten seconds free of anything that is not the promise. Brand frames, slow pans and a greeting are where most business content loses the audience it had.

The five shapes that get passed on

Shape	What the sender is giving	Where it comes from in a business
The demonstration	Proof, settled in front of their eyes	Anything you make, repair, clean, cook, build or test
The insider rule	Status: they know something now	The advice you give clients that costs you nothing to say publicly
The scale reveal	Surprise, at a size nobody pictured	Volumes, costs, waste, how long something really takes
The useful artefact	Practical help for a specific person	A checklist, a calculator, a template, a one page map
The recognisable moment	Belonging: this is us	What happens in your trade at 4pm on a Friday

Pick one shape per piece and commit to it. A demonstration with an insider rule bolted on becomes a tutorial, and tutorials get saved rather than sent, which is a different outcome and a weaker one for reach.

Make it native to one platform

A piece made for everywhere performs like an advert everywhere. Choose the platform the share sentence suggests and build for it: vertical video with burned in captions and no borrowed watermark for short form feeds, a carousel whose first panel is the claim and whose last panel is the action for image feeds, a thread whose first post stands alone for text platforms, and an article with a quotable paragraph near the top where people link rather than repost. YouTube publishes its own guidance for making Shorts, and the equivalent specification for each platform is worth reading once rather than guessed at.

Two production details matter more than their size suggests. Captions, because much of the audience watches with the sound off. And the first frame or first panel, because that is what appears in the share preview when somebody sends it.

Volume is part of the method

Judge the process on a set of pieces rather than on any one of them. Make twenty in one shape, publish them on a schedule, and read the pattern: which openings held attention, which shapes were sent on, which subjects produced comments worth answering. That pattern is the asset. A single piece that travelled tells you much less than twenty pieces that show you which of your subjects people want to pass on.

Batching makes this affordable. One afternoon of filming in the workshop produces a month of short pieces, because the expensive part is setting up rather than shooting. Write ten share sentences first, then film to the list.

Measure sends, not likes

• Shares and sends per thousand views. The only number that describes passing on. Track it per piece and compare across your own work rather than against anybody else's.
• Retention through the first three seconds. This measures the opening, and it is the fastest thing to improve. Platform analytics show it directly, as in YouTube Analytics.
• Saves. Useful artefacts get saved. A high save rate with a low share rate means you made a reference, so make the next one easier to send.
• Comment substance. Questions about the thing you do are worth more than praise, because they are next week's content and sometimes this week's enquiry.
• What happened on your own site. Branded searches, direct visits and enquiries in the days after a piece travelled. Reach that moves none of these was entertainment.

Keep the business inside the frame

Reach only pays if the viewer can tell who did the thing and what to do next. The product or the work should be visible in the piece rather than announced at the end, the name should be legible without a logo sting, and the destination should be one place with one action. A piece that travels while the viewer learns nothing about who you are is a gift to the platform.

Length, frequency, dull industries and the week afterwards

How long should a piece be?

As long as the one idea takes and no longer. Short form rewards getting to the point, and a demonstration that takes forty seconds should take forty seconds rather than being padded to fit a guess about the algorithm.

Does posting more often make a piece travel further?

Frequency gives you more chances and more data, which is why it belongs in the method. The individual piece still has to earn the share on its opening and its one idea.

Can a boring industry make content that gets shared?

Yes, and often more easily, because the insider rule and the scale reveal are strongest where the subject is unfamiliar. Pipe surveys, grain drying, warehouse racking and tax deadlines have all produced pieces people sent to each other. What travels is the specific thing nobody outside the trade knew.

Should you pay to promote a piece that is already moving?

Putting budget behind a piece that is being shared organically extends the window and buys you the audience the sharing already validated. Keep the two reports separate so you can still read the organic share rate afterwards.

What do you do with a piece that travelled?

Answer every serious comment on the day, publish the follow up the comments asked for while the attention is there, and make sure the page the new visitors land on explains what you sell. Most of the value in a piece that travelled is collected in the week afterwards.

What a spike does to the questions people ask about you

There is a second wave after a piece travels, and it is quieter. People who saw it go and look you up. Some type your name into Google. A growing number type it into ChatGPT, Gemini or Perplexity and ask the obvious follow up: who are these people, are they any good, what do they charge, where are they based. The piece created the curiosity and something else answers it.

That answer is built from what those systems can read about you, which is your own site, your listings, review sites and whatever anybody has written about you. A business with a thin trail gets a thin answer at the exact moment its audience is biggest. So the week before you publish the piece you expect to travel is a good moment to check what the assistants currently say when somebody asks about your business, and to fix the gaps the answer reveals. Ask each assistant about your business the way a new viewer would, write down what it says and which sites it credits, and fix the thinnest one before you publish. AI Knows Us does that job on a list of questions you set.