Listen what questions are asked. Usually the more questions you hear the better. Sure, sometimes you’ll be killed with a number or type of questions and then it doesn’t help the candidate any more. Anyway, generally it works.
Another important thing is what exactly you’re asked about. It happened several times I had quite an insightful discussion about our products or our market with a candidate and it was always a sign of interviewee’s real interest in a job. It also tells you something about their knowledge and approach.
As often, there’s no silver bullet here, but when you listen carefully you will find at least a couple of hints when you are asked questions on interview.
Whole avoiding hiring mistakes series.