With your exam tomorrow, what do I do in the last few hours ? 

Answer is nothing. I would say do not read anything after 6-7pm today. Just relax. Talk with your friends, do time pass, talk to your mom. Have your dinner around 8pm  and sleep by 9 max. Nothing beyond 9. 

You need a very very fresh mind to give an exam for 3 hours. In the last few extra hours you are not going to read anything/revise anything/achieve anything.  So turn off your mobile by 8pm. !

Prepare a Check List and add what you need in extra. Basic things are
Take your needed documents for tomorrow
Safety -  mask and sanitisers needed

Best wishes :) You will do well. Your 5 years of knowledge backs you and you do not need anything more !