i think u mean carry on as in the liquid stuff right? well jeanie provided a link but recently.. i think it's still the 3 1 1 rule here's a link
http://www.tsa.gov/311/
3 ounce liquids or gel i.e. gels, lotions, toothpaste
1 quart small zipper bag [like a sandwich size]
1 zipper bag per traveller
when i traveled to and from thailand... i found the best thing to do is put even your lipgloss in the bag because u can get it thrown out if it's not in the bag because it's considered a soluable liquid substance. DO NOT bring big size lotions, creams, deorderant, gels, hairspray can, and u get my drift? if you think u need to bring shampoo, soap, toothpaste, get the trial size from walmart or something for $1 each, that's what i did for toothpaste and stuff because when i stopped over at Japan, i felt i needed to refreshen up by showering but, brushing just my teeth for that time was also ok. i believe that once you're in the airport having lay overs and stuff, u can buy food or beverage and will be able to bring it on the flights with u. i was able to do this and i flew american airlines.
as in for what to carry your passport and stuff. after only 2 trips, first one was messy i didn't know where things were and stuff because i had a big bag and just stuffed everything in there. 2nd trip... i made sure i had my passport and boarding pass in an easy accessible area, like a small purse with a slot right up front, so i don't go insane looking for these 2 things over and over again.
and yes i'm one of those people who did bring soap from here to use in thailand haha... i don't like their soap so i brought 2 bottles of my dove body wash to thailand. and some hair leave in conditioner. hmm i don't remember what else, but on my first trip i also brought mouth rinse, shampoo, conditioner hahaha but i found dove's shampoo in thailand was better so i didn't bring those on the 2nd trip lol
any more questions just ask haha