You need to read your thesis, write some notes, rehearse for the viva and so on. You need to prepare for your viva, but preparation is only a part of getting ready.
You need to build your confidence for the viva; that can be based partly on your practical preparations, but is also done by reflecting on your progress, your success and your talent.
You also need to rest. You need to recharge. You need to relax. Making time to read and reflect can already feel tricky, but you still need a break too. You need time to just be yourself.
Plan your prep. Build your confidence. Rest and recharge.