Test taken: Sixth Term Examination Paper (STEP)
Number of interviews: 2
Time between interviews: ≈ 4 hours
Length of interviews: About 30 mins
Online interview: Yes

Both interviews had very short discussions at the start as to why I wanted to study maths and why Cambridge as well as my favourite aspect of maths, though I suspect it was more to release some tension at the start rather than actually evaluate my suitability as a candidate.

I then proceeded to do some questions, talking through what I was thinking and why I was doing the things I was doing and whenever I seemed stuck or going in the wrong direction (most times) the interviewers would give me a hint to try and redirect my efforts. But I was never able to complete a single question as they would stop me right before I got to the answer and move on to the next question which was painful but necessary to really see as much of my ability to think as possible I suppose.

I was also asked briefly about a book I mentioned in my personal statement (I had written about a section of the book that I really found interesting and had to explain why I thought it gave me a perspective I hadn't taken on a certain topic as described in my personal statement).

I had already started preparation to the step and had done some MAT/Senior Maths Challenge prep before too which made facing unseen material and challenging questions much easier but I was lucky enough to have a previous student from my sixth form who had also gotten an interview from Cambridge give me a mock interview as well as another mock interview from a school that offered mock Oxbridge interviews to state school students. I think one of the most impactful aspect of my preparation was watching pretend interviews on YouTube from Cambridge to get an idea of what was expected and I pretended to be the one responding to the interviewer (I would pause the video after every question they asked/bit of feedback and pretend to respond to it).

Cambridge had some preparation material that helped at the very start as well as a couple of webinar series but mostly past papers questions from archives.

Give it your best, best case you get in, worst you are way way prepared for any other course in any other uni so might as well give it your best shot, plus you don't want the regrets of wondering what would have happened had you done more. Also don't worry about thinking you won't get in, this shouldn't matter to you at any stage as much as trying your best and enjoying the (sometimes painful but worth it) process.

The interviewers are very much looking for someone who is able to express their thoughts and respond to feedback so if you are able to, try and say out loud everything you are thinking as you do the interview and do not be scared to ask any questions no matter how stupid you may think it is during the interview, it's better to do that and clarify something to move on rather than get stuck for 10 minutes trying to figure out what the interviewer meant.