0.segment/L.the.L
After the cutscene, go to 2F and head to your classroom, 2-A.
After class, go to the foyer in front of the stairs to find 3 people gathered. Talk to the editor and say yes.
Go to the 1F east corridor to see an event with Sakura and Shinji.
Go past the schoolyard to the archery range and talk to Taiga.
Then, go home.
Go talk to the editor again in the same place as yesterday.
Speak to Rin on the roof. You can get there by going up the stairs from 3F.
Then, go home.
Talk to the editor again.
Go past the 1F east hallway out to the garden and see Kuzuki.
Then, go home.
Talk to the editor again.
Go to the 1F east hall to see Shinji.
Go to the library. You can find it in the 2F east hall. Check the bookshelf marked with "?".
Go to 1F and follow Leo to the west. Check the wall after he disappears.
After the event:
Choose your gender, your name and nickname, and your Servant. 1st is Saber, 2nd is Archer, 3rd is Caster. It confirms your choice twice.
Follow Leo down the 1F west hallway again. Check the wall after he disappears. You definitely want to know.
Work your way through the tutorial area. Pay attention—you need this stuff to survive.
After the tutorial, you get a fake boss fight. It doesn't matter whether you win or lose—the story decides you lost either way. Refuse to give up when asked. Twice.
Now, revenge time.