Try first to substitute his least favorite feeding first. If the baby won’t accept the bottle from you, (he knows the breast is right around here somewhere) see if a support person can succeed. It may also be helpful to have you not in the room/home so baby cannot smell you. Let the baby have a few days (or weeks, if possible) between each time you substitute a breastfeeding session with a bottle. Express a little milk from your breasts, to your own comfort, if you become engorged. Don’t express a whole feeding’s worth of milk; just enough to take the pressure off. Your body will get the signal to make less milk over time, slowly.