A common approach is to describe the functionality aloud. If your description includes the word 'and', then there may be a problem ("this method increments the foo counter, and makes the tea").
It is the minute details that are sometimes the problem. For example, if a developer is iterating over an array to do something to each element, there is a good chance that that iterator should be separated out in the event that it may be reusable (if using something like map).
