Linguistics Admissions Assessment (LAA); 2x interviews
Interview 1: discussion of how linguistics interacts with other disciplines; Interview 2: translations, personal statement
Re-read sections of books mentioned on personal statement
Olympiad questions
Your interviewers are well aware that you haven't studied the subject before
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.
Test taken:
Number of interviews: 2
Time between interviews: 1 hour
Length of interviews: 15 minutes
Online interview: No
The first interview wasn't subject specific, it was lead by an Egyptologist and (I think) a historian. So we spoke about how other areas interacted with linguistics: sociology, history, politics, technology. A lot of that was talking about my opinion on current affairs or philosophical issues that related to language and being able to back it up.
The second one was very linguistics specific. I was asked to read a set of sentences alongside English translations and then identify what I thought each individual word meant. We then spoke a bit about the things I'd written in my personal statement and what I was looking forward to studying (this is where the preparation came in most useful). None of it was as scary as I thought it was going to be!
Doing research into the things I'd mentioned in my personal statement so I was able to elaborate on the examples I had only mentioned briefly and show I knew something about the languages and studies I'd spoken about. I mentioned a couple of books in my personal statement: rather than flicking through them, I read the bits I found most interesting in the car on the way. That way, I was able to show I was passionate about something and had bits I knew I could lead a conversation on fresh in my mind.
Practice papers from the University Website and a few Linguistics Olympiad questions (also found online). The University practice papers were more useful because they showed the layout of the test and gave an accurate insight into the difficulty and style of question. The Olympiad papers were useful for the translation and logic exercises, but the Olympiad questions were LOTS harder than the ones on the assessment, so don't let them worry you.
I was absolutely terrified I was going to be asked a question I didn't even understand, that linguistics was going to be somehow different to what I thought and justbe out of my depth. You don't need to have this fear. Your interviewers know you've never studied this before: in my case, two of them hadn't either! Everything they asked was either personal statement based or asking my opinion on something, so I couldn't go too far wrong. As long as you can back up what you say with some sort of reasoning, you'll be okay. If you feel like one or two answers were weak or unsubstantiated, that's totally okay: there's a reason they ask so many questions!