-Don't forget to pack your own shampoo, deodorant, etc. There are a number of copy cat brands in China, so buyer beware. I have seen people purchase what they thought was a North American or European brand of shampoo and the contents where not and it was very damaging to their skin/ hair. Also, makeup as well as personal hygiene products are two or three times more expensive than what we pay for them here in North America. Stock up on what you need before you go -- if you have extras leave them for new friends at the close of your trip.
-Bring Tiger balm: It depends on where you are going -- some restrooms in China are still pretty primitive -- so be prepared. Take your own toilet paper and seat covers for where the toilets actually have seats. Most public toilets are the squat type so start exercising your thigh muscles and practice squatting. A small dab of Tiger Balm under the nose can be very helpful in dispelling unpleasant odors in the toilets.
-Do get a China cell phone rental so you can stay in touch and coveniently get important information during your stay.