Mini kite fold worked well when dd was small. I didn't use flats when she was a NB, but started maybe around 6-7ish months. She was only about 12/13 lbs at that point, so she was still little. There is a thread around here somewhere on different types of folds, just do a search for "flat fold tutorial" and it should pop up.
I lift my eyes unto the hills, Where does my help come from? My help comes from the Lord, The Maker of Heaven and Earth. And I'll praise You in this storm and I will lift my hands, For You are who You are no matter where I am, And every tear I've cried You hold in Your hand, You never left my side and though my heart is torn, I will praise You in this storm