Don't forget,small talk does not always have to be unrelated to work topics. It may be semiwork-related as well. Questions about what kind of work projects the other person has been involved in or their professional specialization are always interesting conversation fodder. The key thing about small talk is to be genuine, and react in a natural manner. Ask questions about the things the other person mentions that are genuinely of interest to you rather than the things you think you are "supposed" to ask about.
  Show interest and enthusiasm. Don't be afraid to digress on seemingly unrelated topics. The aim is to discover common interests and enjoy the interaction. If you and the other person discover that you both are fans of the Isle of Hawaii as a vacation destination, for example, that's a start and surely you will find other things in common too. And above all, avoid being overly earnest be a real person. Be relaxed, smile and be a pleasant person to be spending time talking with. In The American-style socializing the following are some pointers for business lunches and after-work socializing.
Avoid drinking alcohol at lunch (the "three-martini lunch" of past decades has long been out of style!).

Avoid drinking too much alcohol at after work functions. Although in Japan drinking is de rigueur, in an Ameri- can-style social situation, it's better to avoid alcohol, so that you can keep your wits sharp and be a good conversationalist. Probably better to save the drinking for when you are kicking back with personal friends.

The host should pay for the meal as well as other charges such as a tip for the hatcheck. In the U.S., the preferred seat for the guest is the one with the more desirable view. "Ladies first" rules in the U.S. are less strict nowadays than many Japanese have been led to believe but are good to follow to the extent possible, for example, holding doors for women, holding chairs for women, helping women on with their coats, and allowing women to enter and exit elevators first.
  Mingling, there's an art to circulating at a cocktail party-type function. Strike a balance between talking to people long enough to make a connection, but not "glomming onto them" and monopolizing their time.
 The goal at a cocktail party is to meet several people and make connections that can be followed up on later if there appears to be mutual interest. This means that sensing when to end the conversation and move on to the next person is important. The key question to ask yourself is: Is this a meaningful conversation or does it reek of a sense of duty? If you are feeling bored or the other person looks as if they are feeling bored, it's time to say
"if you'll excuse me I must go and mingle" and gracefully break off the conversation and move on to talk to someone else. By following the above suggestions, you are sure to forge many useful business relationship.