Sterilise the containers that you are going to express milk into and store milk in. Make sure they are clean first, then boil them for five minutes or soak in sterilising solution.Express milk straight into sterilised containers.Store milk in sterilised plastic or glass. Plastic is better for freezing.Cover the container and keep it in the back of refrigerator where it is coldest (not in the door).Milk stored in the refrigerator is best used within 48 hours.Frozen milk will keep for 2 weeks in a freezer section inside a one-door fridge, or for 3 months in the freezer section of a fridge with a separate door, and for 6 - 12 months in a separate deep freeze (write the date on a label on the container).You can add more breastmilk to a container in the freezer if you chill it in the fridge first. It will only keep for as long as the OLDEST milk in the container.