X is a conversation surface, so templates optimise for replies
On most networks a template optimises for a save or a click. On X the useful currency is a reply, because a reply is what pulls a post into other people’s timelines. That changes the shape of a good template: it has to leave something for someone else to say.
This is why so many imported templates underperform here. A post that answers its own question completely is finished, and a finished post is a dead end. The structures below all end somewhere a reader can pick up.
Five structures worth keeping
The specific disagreement. State a common belief in one line, then say plainly why you think it is wrong. This works because it gives people something to argue with, and it fails when the belief you pick is a straw man nobody actually holds.
The worked number. One real figure from your own work, then what you changed because of it. The figure has to be yours; borrowed statistics read as filler and invite a source request you cannot answer.
The short list with a gap. Three or four items, deliberately not exhaustive, ending with an invitation to add the missing one. The gap is the mechanism, so leave a real one.
The before and after. Two states and the one change between them. Keep it to one change: two changes and nobody knows which mattered, including you.
The question you actually want answered. Not a bare request for thoughts, but a question with a constrained answer space, because a question that could be answered a hundred ways gets answered zero times.
What the long-form limit changed
For years the constraint was 280 characters and every template was built to fit it. The much higher limit removed that constraint, and the result is that length is now a choice rather than a rule, which is harder. A long post has to earn every line, and most do not.
The practical version: write it at whatever length the idea needs, then cut until removing another sentence would remove information. If the finished post fits in 280 characters, post it there. Length is not a signal of effort.
The image shape, which is not optional
X shows 16:9 inline without cropping, which is why templates for this network are landscape while nearly everything else is portrait. A 4:5 graphic posted here gets letterboxed and shrunk, and the text that read fine on your monitor becomes unreadable in a timeline.
One useful side effect: 1200 x 675 is also what a YouTube thumbnail wants, so a single design covers both. Worth knowing if you publish to either.
The character maths nobody tells you before you write
A template that fits on your screen and not in the post is worthless, and X does not count characters the way you do. A URL counts as 23 characters whatever its real length, and an emoji counts as two. Our own publisher validates every X post against 280 characters with those rules applied, and trims at the nearest sentence boundary rather than cutting mid-word.
Write your templates against that arithmetic rather than against a character counter that treats a 60-character link as 60 characters. The gap is where a template that looked fine gets truncated in the feed.