The best idea that we’ve had about traveling with young children is to pre-pack each day’s clothes in plastic freezer bags and label them for each day. Include the entire outfit from underwear, to socks, to shirts, to shorts or pants or skirt.
This may require a little more pre-departure work, but it makes our vacations much less hectic when dressing the kids in the morning. Each child gets their bag and puts their clothes on, and out the door we go. This avoids pulling the suitcase apart and trying to find each neatly arranged article of clothing.
Bonus: It also helps ensure we don’t forget anything important at home.