This is how you get stuff done.
THINK about something until you decide what to DO, then DO something until you need to THINK about it some more.
-OR-
DO something until you decide you need to THINK about it, then THINK about it until you DO some more.
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Start somewhere, PAY ATTENTION while you THINK and PAY ATTENTION while you DO, don't sweat it if you're not right yet, and keep going.