How many words fit
Most narrators speak about 150–170 words a minute in English. For a 60-second video, aim for 130–150 words so there's room to breathe. Some languages are faster or slower - Spanish and Japanese, for example, usually need fewer words for the same time.
A structure that works
Hook (one sentence): open the question.
Setup (two or three sentences): the context the viewer needs - who, where, when.
Turn (two or three sentences): the surprising part, the twist, the reason it matters.
Payoff (one or two sentences): answer the question the hook opened.
Close (one sentence): a thought to leave with, or a reason to watch the next part.
Write for the ear
Short sentences. One idea each. Words you'd say out loud, not words you'd write in an essay.
Read it aloud before you record. Wherever you stumble, the viewer will too.
Write for the picture
Every sentence will need a picture. If a line is too abstract to show ("this changed everything"), make it concrete ("within a year, every ship carried one").
An example
Hook: "In 1932, Australia declared war on emus - and lost."
Setup: "After the First World War, veterans were given farmland in Western Australia. Then 20,000 emus arrived to eat the wheat."
Turn: "The army sent soldiers with machine guns. The emus scattered, regrouped, and outran them. After a month, the soldiers went home."
Payoff: "The birds were still there. The farmers built fences instead."
Close: "It's still remembered as the Great Emu War - the only war won by birds."
That's about 90 words: room to slow down on the twist and let the pictures land.
Editing your script
Cut every sentence that starts with "Interestingly", "In fact" or "Did you know". The fact is interesting or it isn't.
Replace general words with specific ones: "a lot of birds" becomes "20,000 emus". Specifics are easier to picture and more believable.
If two sentences say the same thing, keep the shorter one.
Checking facts
Check every name, date and number against a reliable source before you record. One wrong fact in the comments can undo the trust of the whole video.
Keep a note of where each fact came from. If someone challenges it, you can answer - and the description is a good place to credit your sources.
Questions
Should I end with 'like and subscribe'?
A brief ask is fine, but a reason to watch the next video works better than a generic request.