Its pretty much been said, but for you...
Pj's, loose comfy clothes, towel, toiletries, breast pads, sanitary pads, camera, snacks, magazine/book, money, tense machine & spare batteries (if you are having one).
For baby...
x3 vests, x3 outfits, nappies, cotton wool, wipes, hat, blanket, car seat.
Any labour aids you might want, for example...
Essential oils for either a massage or to smell, lucozade glucose/energy tablets if you dont feel like eating but want to keep your energy up. Evian water vapouriser, they are great for cooling you down if you feel hot or sick and can be refreshing to give you a little boost.
Good luck.x