While it is customary to give gifts, there are a few customs that are tied to gift giving. First, one should never offer a gift with the first offer. If is acceptable and expected that you would accept the generosity of the gift-giver but not the gift. At least 2-3 declinations of the gift are expected. It is expected that the gift-giver is perservering and will try to bestow the gift as many times as it is declined. If the gift is finally accepted, it must be with much resignation so that the gift-giver experiences a sense of victory from being able to bestow the gift. The gift must be accepted with much gratitude and humility.
It is very acceptable to "wash" your dishes with tea before you have the meal. Typically, this involves pouring the first tea into your tea cup and giving it a good swish. Pour this into your rice bowl and invert the tea cup and run the lip into the hot tea. The chopsticks are then dipped into the rice bowl. The residual tea in the rice bowl is then poured out into the "waste" bin for the "wash."
There are a few that should be noted. The first is mentioned in a tip by itself and that is the process of sanitizing your dishes with hot tea before eating.
Another notable table manner is to avoid touching food with your hands. Food should be manipulated and introduced to the palate with chopsticks. This includes delectables such as steamed buns, which could easily be eaten with fingers.
Typically, there are teacups, rice bowls, and small plates that are included in the place settings for the meal. One should note that the small plates are not used for food. This is the discard plate. One should discard any inedibles onto this plate (i.e. bones, skin, paper, etc.)
It is also good table manners to tap the table next to your teacup when being served tea. This signifies gratitude for filling the tea cup. It was related to me that the origin of this custom was from the days of the emperor when he was served tea. He was not to speak, but this was his gesture of thanks.
I am not sure how widespread these customs are and I recommend that they are followed only in southern China. These customs are very acceptable in Taishan and Guangzhou as well.