It’s a good idea to wait until the baby is at least a month old before you introduce a bottle. Any earlier and you may cause nipple confusion and that can be hard to undo.
Many mothers have someone else offer the bottle at first (hello, Daddy!) somewhere other than where they generally breastfeed so that baby doesn’t have his usual feeding cues.
At first, have the person doing the feeding offer a little bit of breast milk an hour or so after a regular feeding so that the baby is more open to experimentation, but not so hungry that he gets distressed.
It may help to drip breast milk on the baby’s lips or tongue to give an idea of what’s to come.
Run the nipple under warm water before giving it to the baby.
If ten minutes have passed and he hasn’t fed, stop trying. Better to stop before baby gets really upset and associates the bottle with frustration.
If he still refuses after a few attempts, you may have to experiment with different nipples and bottles until you find one he likes.