To adjust the grind settings, you'll find a small wheel next to the hopper on the grinder's top. The wheel moves the burrs and adjusts the grind size. You can purge coffee through the grinder each time you adjust the grind size to reduce grind retention. Devices with high retention require more purging to ensure that all ground coffee is fresh. Yet, remember that Eureka Mignon grinders have low retention, so they don't require purging between every adjustment.