What to wear depends mainly on two things; when and where you are traveling. China’s weather varies tremendously with these factors. Winters in the far north are extremely cold and the summers are hot and dry. In the central regions along the Yangtse valley area winters are short, cold and wet whilst the summers are long, sticky and hot. In the southern regions the climate is hot and humid from April to September (when it is also the rainy season) and are affected typhoons between July and September. Winters are short but chilly. The north western desert regions are hot and dry in the summer and extremely cold in the winter. The weather in Tibet is often very cold and very hot in the same day!
For hot weather light, breathable layers are best, and care should be taken to avoid sunburn and overexposure to the rays. Clean water should be taken in at regular intervals to avoid dehydration.
For cold weather layers of clothing that trap the heat should be worn, the outermost of which should be windproof. A hat is also essential in very cold weather. In general a light rain jacket and waterproof walking shoes are a must. Most shopping centers and hotels are air conditioned at quite low temperatures, making it necessary to be able to dress fairly warm during the summer as well.
At some of the monuments and temples, it is advisable to avoid sleeveless tops, short skirts, and shorts.