What to bring
As little as possible. It is much better to buy things as you need them than to throw things away because you have got too much to carry. Lightweight and compact are two words that should be etched in your mind when you are deciding what to bring. Drill hokes in the handle of your toothbrush if you have to , anything to keep the weight down.
That advice having been given , there are some things you will want to bring from home.
Chinese-made backpacks are often found to be of poor quality. Investing in a good backpack is one outlay you will never regret. Look into buying a frameless or internal-frame pack, these are generally easier to store aon buses and trains and also more comfortable to walk with. Also consider buying a pack that converts into a carry bag by way of a flap that zips over the shoulder and waist straps, it is less likely to be damaged on airport carousels and is more presentable if you ever need to discard the backpacker image.
A day pack is essential for carrying things around after you have dumped your backpack at the hotel or railway station. A belt pack is OK for maps, extra film and other miscellanea, but do not use it for valuables such as your travellers cheques and passport, it is an easy target for pickpockets.
If you do not want to use a backpack, a shoulder bag is much easier to carry than a suicase. Some cleverly designed shoulder bags double as backpacks by re-arranging a few straps. Bring suitcases only if you know you won't be carrying your luggage on buses and trains.
Theoretically you need only two sets of clothes, one to wear and one to wash. Dark coloured clothing is preferable because it does not show the dirt, white clothes will force you to do laundry daily. Clothing is one of the best cheap buys in China, so don't feel compelled to bring everything from home. China is pretty informal, although fashionable clothing is in vogue in Hong Kong, Beijing and Shanghai. Shorts and T-shirts are respectable summer wear, but try to look clean. Flip-flops (thongs) are not acceptable for outfoor wear, but sandals are OK.
If you are travelling in the north of China at the height of winter, prepare youself for incredible cold. Good down jackets are available in China, but it is hard to find good quality hats, mittens and boots. (at least in western sizes). Western long johns are more comfortable and warmer than the Chinese variety.
C. Sleeping Bag
A sleeping bag is required in China only if you are planning to go camping. Hotels provide copious bedding during the winter months, as do the sleeper carriages on trains. Even in Tibet, you can do without a sleeping bag if you are going to be staying in hotels.
Absolutely essential is a good pair of sunglasses, particularly in the Xinjiang desert or the high altitudes of Tibet. Ditto for suncreen (UV) lotion. A water bottle can be a lifesaver in the western deserts.
Outside the major cities, some pharmaceutical items are hard to find, such as shaving cream, decent razor blades, mosquito repellent, deodorant, dental floss, tampons and contact lens solution. An alarm clock is essential for getting up on time, make sure it is lightweight and bring extra batteries. Size AA rechargeable batteries can be bought in China, but the rechargers are bulky, bring a portable one and plug adaptors if you cannot live without your Walkman.