when you are in a social event, it is important that you talk to as many people as possible. not only because you want to make the most out of this social event and know more people, but also this is a way to show your politeness

it is rude to stick to yourself not to social at all

it is rude to stick to someone all the time but not to talk to others or let others talking to this party you find so interesting to talk to

it is rude that you sit there and eat, ignore the people seated in both of your sides. you are responsible to talk to both of them as they would have to talk to you

but you do nto talk when your mouth is full. so you talk when you are not chewing on your food….

when you see someone there quiet all by her/himself, it would be nice you walk over and talk a bit to her/him

keep a proper distance between yourself and the other party, not too close.

try not to use too much body language around the people you do not know well like a pat on the shoulder. i personally hate it when strengers do that to me. what i hate the most is another guy pat on my lap when we both sit and talk. trust me, it is not the same as from an attractive lady. so you would not want to do that to another guy if you are a guy.

some southerners here like to do some of that or shake your hands really hard to show their style as a real man. if you are chinese, you do not need to copy that. we are or once were known for being elegant and subtle.

always introduce yourself before talking to another party.
always introduce a joining party to the party you are talking to, and vise versa.

do not talk too long on the same subject, unless you see the excitement from the other party.

if you are with a group, make sure it is not just you and one other talking, find a common subject all others could join in and participate.

ask those are a bit shy on what may bring them into conversations

do not stick to subjects most others have no idea or interests, only you know and thus want to show off with.
people will be polite for a few minutes but then they will find excuse to leave you there by yourself

always pay attention to the reaction of your audience as to determine how much further down you want this subject to continue

if you are joining another group, don’t just cut in, wait for the timing where you can naturally ease in.

do not show off too much for too long, or you become annoying. it is OK to impress others for a while, but watch closely with great attention to observe, when you see a propotion of your audience began to lose interests, it is time for to ask someone like “so, how is everythign otherwise in your world?”