I stayed there for two months this year
depending on where you are the culture varies a lot, mainly by the size of the city
culturally expect a shock at how pan-faced people can be, it takes time to get to know chinese people.
This can be compounded with the rockstar/zoo animal/alien treatment you get, people will take photos of you all the time but have limited interest in actually getting to know you
coughing, spitting, kids pooing in the street, constant yelling at mobile phones, everyone calling you "gwailo/lowai/laowaa" like you can't understand.
you just have to wear a mask and deal, I currently have tonsillitis courtesy of Chinese respiratory hygine
start doing things on your mobile, get a chinese sim card
tan-tan (chinese tinder), tao bao (chinese ebay), wechat/weixin (chinese facebook), baidu (chinese google)
wechat is especially useful as it has one of the best translators for chinese built into it
young chinese people live on their phones, even compared to western kids
trains are good, but cheap seats are awful because of the kind of chinese person that buys them
if you are getting a soft sleeper consider just flying
"greed" is not something chinese understand, it just isn't.
haggle hard on everything except groceries
the t part about this is keeping your temper when everyone is trying to rip you off; it' not personal
I was actually writing a brief guide on travel in china