ClunkintheUK

I found a really useful book when I started my interviews out of uni. The basic gist of it was, figure out what your USP is. What one thing makes you stand out as suited for the role, ( mine was quick leaner) Then think of three or four themes from your CV that back up this USP, I showed my masters, diverse experience for a fresh graduate ( gap year and internship and even my uni work in a bike shop) and the highly numerate degree (it was a technical role) then for each theme think of 4 examples or situations that back up that theme.

From this you should have written down on a piece of paper a pyramid three layers deep. Each story at the bottom is a potential answer to a queation. So then think about what the likely questions are and how each of your potential stories would answer this. A story can respond to more then one question, and you can have more then one potential response. Each response you then give should ultimately link up and bolster your USP without you having to actually articulate it directly. They will likely have to ask the same questions of each candidate, so using the same response twice is not necessarily a problem, just saying 'as I mentioned before' and you can give a shortened response just highlighting why it is relevant to the current question.

I also found having a mechanical way of preparing for the interview meant that I was much less nervous, and when the curve ball came up that I hadn't thought off had a bank of 15 or so situations that I could pick from, or as in your case I'd have those three qualities backing up my USP directly at hand to respond.

I have also found it useful to write down on a piece of paper all the questions I want to ask the interviewer. That way you won't forget, but also when they ask if you have any questions, you can check your notes, and if everything as indeed been answered in the interview already, you don't look unprepared.

This has always worked for me in interviews, but for the record I have never been and interviewer.