Circle the brush inside the bottle several times. Be sure to use the included nipple brushes to get into the hardest to reach places. And finally, don't forget to clean your cleaning tools! Always rinse brushes thoroughly and run them through the sterilizer or dishwasher at least once every few days.
Clean wash basin and bottle brush. Wash them every few days, either in a dishwasher with hot water and a heated drying cycle (if they are dishwasher-safe), or by hand with soap and warm water.