More things Rose did, aside from reading, to prepare for interviews:
If you’re feeling a little more adventurous and if you can sort transport, travel to different museums or other similar sites. Personally, I’ve always wanted to go to the British Museum (to see the Parthenon sculptures!) but never quite managed it, although I have been to The Ashmolean.
You can make some (sometimes surprising links) between your subject and other subjects: I spend a lot of time at a National Trust property called Moseley Old Hall (partly because I work there ahaha), and even though Moseley is a 17th Century farm home that has nothing to do with Classics, whilst learning about the conservation techniques there for, say, their pottery collection, I’ve found plenty of crossovers into my subject.
A fair few museums, and even more universities, also offer Yr 12 study days, or at least masterclasses, usually lasting for a morning or afternoon session. A quick Google search shows a huge range of subjects at many different places, from Classical Civilisations at Cambridge to Jane Austen’s World at The Ashmolean, or Transport Management at Aston! These vary in cost from free to a nominal fee of around £10. Randomly, I did a Transport Management masterclass at Aston (not useful at all for my UCAS application, but it came in so handy for my Geography ALevel) and as it was run in conjunction with Centro (a transport company in the West Midlands) I got a free bus and train day ticket to Birmingham!
Finally, perhaps the most important thing you can do is simply talk to other people about your subject (to be honest, if you’re enthusiastic about your subject then you’ll probably want to do this anyway). It doesn’t matter whether they know anything about your subject – I talked to my UCAS adviser (a history and politics teacher, not a Classics teacher). I also talked to my Classics teacher and Classics buddy in class, and I was also fortunate to work with someone (still do) who did History of Art at uni, and so was always up for a chat about Classical art and anything else I wanted to mention.