Tourism
When travelling throughout China, you'll want to keep in mind that it's a vast country with a wide variety of culture, customs, and economic levels. You'll find first world atmospheres in the big cities like Beijing and Shanghai, but travellers to rural China will find that the locals still live in third world conditions. You'll also want to keep in mind the recent economic incline, which caused rural migrant workers into big cities, a lifestyle many haven't become accustomed to.
To get in, you'll need a visa. This isn't normally a problem for Western tourists, who don't need an invitation and can acquire a visa for around $25. Visas are typically valid for thirty days and must be used with in three months from the date it was issued. You may be able to get one on arrival.
Major airlines fly to Hong Kong, Beijing, and Shanghai, but not often. It's best to book flights as early as possible, and the busiest times are at the beginning and end of summer as well as during the Chinese New Year.
China does not recognize international driver's licenses. It's best to not drive in China unless you know the customs, anyway. Additionally, Chinese drivers won't stop for you as you cross the street, so be careful. It's best to use an overpass.
Things to look out for:
There aren't many beggars in China, as it's considered shameful, but you'll experience many people offering menial tasks for compensation. It's best to ignore them. Beware of people (usually girls who speak English well) who offer you a "free art gallery tour" . They'll take you to a run-down store and pressure you to buy whatever's there. Also, some bars may try to rip you off by selling you a drink on a menu showing one price, and then charge you a ridiculous price from a different menu.
You'll also want to keep in mind that squatting toilets are prevalent in China. There are often no doors on stalls, and people will watch you do your business. If you're uncomfortable with the idea of a squatting toilet, it's best to use the bathroom at your hotel or at tourist sites, or better yet, have a local host with a clean, sit-down toilet.
There are no health regulations in restaurants, but food is often prepared in front of you. You must boil water before drinking it, or buy it bottled (no more than 3 yuan for a bottle).