As a PhD candidate, I think you have two main strategies to manage how you feel about your viva.
Option One is to try and squash down any nerves that you feel. Take any worries and anxieties and just push them down, lock them away and avoid them at all. Don’t engage. I’ve seen viva success follow from this approach, but at a cost to candidates’ state of mind. I wouldn’t advise following Option One.
Option Two is to work to boost your confidence. Recognise your ability, work to prepare for the viva, notice your talent and where it comes from. Doing this will far outweigh any nervousness you feel.
Nervousness and confidence are not polar opposites – they’re different things all together. You can be nervous about the viva, because you recognise that it matters, yet confident in your success. You only have so much energy and effort available. Rather than focus on squashing away nerves, work to boost your confidence. Confidence will put your anxieties into perspective.
Option One: squash nerves.
Option Two: boost confidence.
Go with Option Two.