You don't; this is not CTR reportable. This scenario is addressed in FinCEN's guidance somewhere (the FAQ I think).
If you see any large checks that, if combined, would equal over $10,000, I would document payees on the report. This can be problem with some businesses (such as real estate agents) and with employee bonuses at the end of the year.
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Life without Jesus is like an unsharpened pencil - it has no point.