I like to go thru my baby bag once a week to restock! Makes it easy and i always know that i have what i need that way. As for whats in it-

nappies- about 8
a plasitc zip lock bag with bum cream, cotton balls, and tips.
Wipes
Nappy sacks- for dirty nappies and soaked clothes!!
clothes- a few shimmi shirts, a good outfit and a wondersuit, a hat and some socks JIC
Bibs- about 3
a dummy
and a face washer or 2, a cloth nappy and sometimes a blanket or wrap, but they are extras that i put in if i need

I find ive always got what i need, and never have anyproblems... hmm this sounds like a lot, but ive got a really beautiful bag that a friend gave me and it all fits in with room to spare!