2x interviews (30 mins each; 2 interviewers each); 2x pre-interview tests (30 mins each; 1 text-based, 1 music-based); 1x test
Interview 1: based around the pre-interview text; Interview 2: submitted essays, compositions
Read around topics that interest you; practise technical skills
You don't always need to have the 'right' answer; don't worry about difficult interviewers
Remember this advice isn't official. There is no guarantee it will reflect your experience because university applications can change between years. Check the official Cambridge and Oxford websites for more accurate information on this year's application format and the required tests.
Also, someone else's experience may not reflect your own. Most interviews are more like conversations than tests and like, any conversation, they are quite interactive.
Two interviews and one academic test. Each interview with two interviewers. We had half an hour to study a text for one interview and the same time for a short piece of music for the other.
The first interview was based around a text, while the second was based around my personal statement and submissions (composition, essay etc.)
Often my answers to questions would be challenged in the next question, while some questions were definitely expecting me to bring in knowledge that they knew I had from my personal statement and essay.
Just general reading in areas that interest you. I had done a significant amount of reading over the summer around authenticity, which I was able to link to many questions.
It's important to realise that you don't need to get all your answers "right" to get an offer. Especially in a subject where it isn't clear what the right answer is.