Clear the hidden chapter: No Applause.
Arrive to the end of the eighth chapter: My way.
Clear the seventh chapter: The lab.
Arrive to the end of the seventh chapter: The lab.
Clear the sixth chapter: The end of the world
Arrive to the end of the sixth chapter: The end of the world.
Clear the fifth chapter: The metro.
Clear the fourth chapter: The theater.
Clear the third chapter: Four cubes.
Clear the second chapter: Escaping.
Clear the first chapter: Wake up.
Clear the mini-game for the first time.
Collect all of the diary pieces.