Visit with your eyes wide open and legs well rested, that’s the only advice I have! You'll doubtlessly be wanting to visit the Sistine Chapel, but before you do make sure to go through the museum. You can take pictures in the museum (except in the Sistine Chapel) where photography is not allowed, though anything is possible, especially if you’re not obvious about it! Monday to Saturday: open from 9:00 to 18:00 and a full entry costs €14 while a reduced entry costs €8. It’s free on the last Sunday of each month from 9:00 - 12:00.