Honestly I didn't really prepare, I dont think there's much you can do seeing as its really up to the baby to do most of the work, you just help her out. I did buy a pump, lanolin, and plenty of breast pads (theyll be your best friend). I also watched a few videos on proper latching technique but my daughter came out latching like a pro so I got lucky.
I do agree with the above though, breastfeeding is painful and that's normal. My nipples were sore and bruised and lightly scabbed for the better part of two weeks. Its rough and it takes dedication, especially if your baby needs helping learning to latch. The best thing you can do to prepare yourself is expect for it to be hard, and plan to handle that.
What I did to prepare my breast for breastfeeding was squeezing the nipple and playing with my breast. I also bought this cream that u apply onto the breast it's made for breastfeeding it helps heal your nipple you can use it during pregnancy as well. I know this one may be kinda weird but I asked my bf to suck on my nipple and I would already start to use the breast pump I know you won't get anything out of it but it helps prepare for the sensation and pain.
It is painful to breastfeed on the first week believe me but don't let that discourage you.
Goodl luck & congrats