Start by turning the rope and stepping over it slowly, without jumping, until the timing is comfortable.
Then move to a two-footed jump. Count out loud together — the count is what keeps the rhythm steady.
Set a personal target rather than a competitive one: beat yesterday's number. Write it somewhere so the progress is visible.
Skipping demands rhythm, timing and sustained aerobic effort at once, and the rope gives instant unambiguous feedback on every miss. Counting aloud externalises the rhythm, which is what lets a child hold the timing before they can feel it.