Exeter Applied Psychology InterviewWatch
I don't know if you've already had the interview? But I had it last year and am studying the Clinical course at Exeter now. Thought I'd give you a few tips from my perspective...
First of all, talk to the other people waiting to be interviewed.. it'll help calm your nerves, and prepare you to speak during the interview. When I went, everyone was sat in silence (for a Clinical Psychology degree interview!!) so I tried to start some conversations which I think helped warm me up a bit. Plus, you may make friends that you'll see when you start the course :-)
In the group interview, in groups of 4 we spoke to a member of the "Lived Experiences Group" which is a group of people with expertise from the perspective of having had a MH problem. We then spoke about another person (we were provided with the information about her before), and her experience of MH problems. Thinking about what you could say beforehand, and any unique answers, may be useful!
Then, we had the one-to-one interviews, where we were basically asked questions similar to a job interview (e.g. why do you want to take this course, do you have any relevant experience etc etc). The people interviewing were the people that you'll see in your fourth year when you do the clinical placement. I was so so anxious and jittery, but still got a place, so don't worry if you think you flopped! It's normal to feel nervous, and sometimes can be a good thing!
It's a great course, I'm really enjoying it so far - good luck!!