What’s Your Problem?
Whenever something viva-related is tricky, confusing or makes you feel negative, your first step is to figure out what the problem is.
What makes this hard? What don’t you understand? Why are you feeling this way?
Once you know what the problem is you can start to do something about it. You could work to make the tricky more simple, the confusing more clear or act to change how you’re feeling. You can ask others to help and even if the problem is big you can take a small step in the right direction.
The work ahead might not be easy, but it’s easier than just trying to cope with stress at your viva. Once you can explain the nature of the problem clearly then you can start to do something about it.
(of course, this kind of thinking applies outside of the viva too!)