Three words that need to be on every candidate’s to-do list for the viva.
The Regulations page I put together – a list of every uni in the UK’s thesis examination regulations – might be a good starting point for some. Given the changes brought on in the last five or six weeks, it’s worth digging deeper with your institution. Check to see if there is anything substantially different. I don’t imagine there will be: the purpose of the viva hasn’t changed, it’s only the medium that’s altered.
There may be constraints that a remote viva forces or suggests, but you know why you’re there and what your examiners have to do. Check the regulations to see if there are any particular conditions that have to be met to satisfy your institution. Ask friends and colleagues about their experiences for a better idea of what to expect.