People talk a lot about pair programming, but when have you ever read about how to do it. What are the mechanics of it? What should a member of a pair do or not

People talk a lot about pair programming, but when have you ever read about how to do it. What are the mechanics of it? What should a member of a pair do or not do? I suspect that a lot of the problem with pair programming boils down to people who don't know how to do it that end up creating a bad social interaction and offending their partner.