congrats, I haven't applied for there, but from what I read here last year, presentations are usually on either current news/events related to teaching OR you have to prepare a lesson plan or presentation to a class as though you were teaching it. After the presentation the other candidates and the tutors there ask you questions so you have to be very quick thinking and ready to improvise stuff on the spot, so not much pre-preparation involved, you just have to be good at responding to questions and being put on the spot. I don't think we are allowed to discuss specific questions (against TSR rules) but its nothing too scary just be confident and speak clearly.