Good advice from all. It seems body language can really help---smiling, as Apathy mentioned, and also sitting in a comfortable/confident position beforehand (& on the phone you can do it while interviewing)---like putting your feet up, hand behind head, the boss in the office look-------I also will write a few things down, key words I would want to use----and if a question is surprising, no harm in saying "I hadn't thought of that, let me get back to it later"---if it still stumps, you can ask if you may call back...showing that you are thoughtful and not just blurting things out is never wrong. GOOD LUCK!!!! (& usually the actual is easier than the anticipated)