Okay so I've now written my own promo packet three times (two got approved, one got deferred) and helped four reports write theirs. I have opinions.
The thing most people get wrong: they write it as a brag document. A list of things they did. That's not what calibration needs. Calibration is comparing you against a rubric, and the people in that room may not know your projects at all. Your packet needs to make the case without you in the room.
What actually works:
Start with the impact statement. One paragraph, maybe two. Not "I led X" but "X resulted in Y, which mattered because Z." The because Z part is what most people skip.
Then match each bullet to the level rubric. Literally quote the rubric language. If the rubric says "drives cross-functional alignment" you need a concrete example where you drove that, not just a time you attended a cross-functional meeting.
For scope: be explicit about the blast radius. How many users, what dollar amount, how many teams. Calibration panels like numbers. Not made-up-sounding numbers, real ones.
For the deferral: I was too vague about scope on a project that was actually pretty high-impact. My manager knew the impact but the other managers in the room didn't. Lesson: your manager is your advocate but they cannot carry the whole thing.
Timing matters a lot too. You want to submit when there's fresh evidence. If your biggest win was eight months ago and the cycle runs next month, that's going to feel stale. Ideally you have two or three strong data points from the last six months.
One more thing: get your manager to calibrate your draft against recent promos at your company. The bar shifts. What got someone promoted 18 months ago might not move the needle now, especially post-2024 layoffs when bar-raising became the response to every headcount freeze.
Happy to answer specifics if you share the role/level you're targeting.