Slowly
There doesn’t need to be rush in viva prep.
Before you get to submission, sketch out a plan. Think about your life, commitments and responsibilities. Plan your prep so the work gets done. Bit by bit. Day by day. Slow prep is much better than racing to pack it all in at the last moment.
No-one has to sprint through their viva.
Listen to each question. Take your time to consider what you will add to the discussion. Ask questions. Check your thesis. There’s no race to get it over and done with. Some vivas are short but no viva has been made better by trying to get through it quickly.
Take your time with prep, take your time with your viva. Slow and steady will take you to success.