The best advice I've ever heard: when you get to a party, look for any group of two people and approach them. Either they both know each other, in which case th

The best advice I've ever heard: when you get to a party, look for any group of two people and approach them. Either they both know each other, in which case they probably know that they should be meeting other people but they're not, or they don't, and so you're probably not interrupting anything terribly important (and you give one or both of them an opportunity to escape a conversation if they want).