It’s unsurprising for me to recommend being prepared for the day of the viva. Often I talk about tips or tools for engaging with research, or ways to look differently at your research. Today I just want to suggest thinking about the day itself. Planning for the day can eliminate decisions you have to make, which can in turn conserve your attention for things that really matter (such as answering questions in the viva).
So what will you do to start the day? When will you get up and what will you eat? Get your clothes ready the night before. Are you doing any more reading, or will you be finding things to occupy your mind? Make a choice in advance. Pack your bag the night before. Decide how you’re going to get to the viva room. Save all of your thinking for the viva itself.
(inspired by a little reading on decision fatigue; have noticed anecdotally that I and colleagues work better when we have eliminated choices in advance)