Knowledge of the local rules and customs is essential to give the correct impression to potential business partners. The following issues need some consideration:
Suits should be worn for business visits. It would be acceptable to wear smart casual clothes to an informal dinner invitation but only do so after establishing that this is how everyone will dress.
Appointments should be made in advance and punctuality is expected. Chinese cities are huge and it is easy is to underestimate the time it will take to cross one in a taxi. Get the hotel staff to advise and still leave a little earlier.
Business visits are best planned so as to avoid the extremes of weather. Your hosts should let you know about local conditions. If you really have to go in summer be prepared for a cold. That's right - constant changes of temperature as you enter and leave air-conditioned areas can seriously affect your health.
Business cards should be printed with a Chinese translation on the reverse and should be presented with both hands, while cards received should be studied and perhaps commented on. It is rude to put a business card directly into a pocket without reading at least the name and job title. It is perfectly acceptable to keep cards on the table in front of you for reference. Never put a business card into a back pocket.
Business visitors are usually entertained in a private room of a restaurant. Guests should always wait for their host to assign their seat. During the meal, the host will toast the visitor. It is a good idea to respond with your own toast later.
Perhaps the most important aspect though is to be seen to be enjoying yourself. A Chinese host has a duty to keep his guests happy and if you don't eat heartily and join in with the table talk then the host will not be at peace. If you have special dietary requirements or any issues about food and drink generally (perhaps you are a diabetic who needs meals at a predictable time) then best alert the host before the event. Such things should be part of the personal information provided for everyone in your group.
It is customary to invite the host or hostess to a return dinner. This should not be at the same restaurant. As the host, you need to remember to arrive first, to seat guests and to toast your guests. You will need to know what food to order and make it clear to staff that you are paying the bill. You can expect Chinese guests to try paying, especially on their home patch. It's all about 'face'.
Most topics are open for discussion. It would be rude to talk about business before and during the food so ask, and prepare to be asked, about family, hobbies and opinions of China. You should bear in mind that the United Nations recognizes the Government of the People's Republic of China as being the only government of China. You may have opinions about Taiwan and Tibet, but best keep those to yourself.
There are many other minor traditions. You should not worry too much about these nor about making a gaffe. A Chinese host would prefer to smooth over any mistake rather than make any issue out of it. Treat any such event as a learning experience and your interest will be looked on favorably.