A mother can start expressing as soon as her milk is established, usually after three to four days. I advise using the Medela Swing Maxi Double Electric breast pump as it will save you a huge amount of time and effort. It’s worth spending the money as hand pumps are tiring and not efficient. If the mother is expressing so that her partner can help with feeds, express before 2pm as the quality of the milk is at its best in the morning. If expressing to relieve engorged breasts, express a little before each feed. If expressing to encourage milk supply, express a little after each daytime feed. But be careful not to express too much or your supply will rocket and you may get engorged, so I would advise only expressing half an ounce each time.
Breast milk can be kept out of the fridge in a cool place for up to six hours, or for up to 48 hours in the fridge. It can then be heated in a bottle warmer or you can stand the bottle in a jug of hot water and test the milk on the back of your hand before feeding. It should be blood temperature and so feel neither hot or cold on your hand.
Always wash and sterilise expressing components and bottles after each use. I advise using an Advent Steam Steriliser.
Let me know if you have any queries.