Equalize before you go in, at 5 feet, 10 feet, and 15 feet - no skipping.
Everyone is different; for me, every 5 feet during descent is not nearly often enough; when I am headed down I equalize every 1-2 seconds. If you wait until you feel the pressure, or worse yet any pain at all, then you're not doing it enough; the pressure differential can pinch off your Eustachian tubes and then you won't be able to equalize.