Ideally, assuming that breastfeeding is going smoothly and Baby has been latching and feeding well, waiting until 4-6 weeks can help make sure milk-supply is regulated and that your baby has a well-established nursing latch. Introducing a bottle around this time is generally easiest because the baby’s suck-reflex is still strong at that time. Somewhere between 6 and 12 weeks, the suck-reflex fades and introducing a bottle can become more difficult.
Of course there are circumstances where pumping earlier than 4-6 weeks out is necessary. For instance, if your baby requires additional milk beyond what direct-nursing is allowing for, pumping milk to use for that supplementation is a great way to have what is needed. If you’re experiencing extreme pain that necessitates healing that directly nursing doesn’t allow or if you’re having challenges with your nipples; pumping and bottle-feeding can be very helpful.
So, if you are in a situation where pumping is going to be a regular part of your breastfeeding relationship, it is ideal to wait about a month to begin pumping. There’s no need to do so daily but rather just get accustomed to what pumping feels like, how your breasts respond to pumping, and gives you time to build-up to regular pumping as you approach your return to work.