In mine i have
2 changes of clothes,
2 cloth nappies for spews
hat
blanket
muslin wrap
dummy
6 nappies
wipes
nappy sacks
change mat (disposable) my bag does have one built in but not used, i only chuck disposable if wee or poo get son it other wise resue.
sudocream

I think that is all i have.

My bag has 1 large section where i put clothes etc and then a smaller section with clear pockets where i keep nappies etc so easy to find.

Mine has a bottle bag and as i am breatsfeeding i put a water bottle in there for me to keep it cool