1: Once you rescue Gail, hop up on the platform to the left of where she was to grab the page there.
2: Once you reach the conveyor belt, there will be a gold wall to the right. Use a laser to bust through it and get the instructions inside.
3: When you reach the elevator door to fix, hop in the shaft and push the cart all the way to the right to make the instruction appear. Hop down into the room and go to the right to grab it.
4: Just after the previous instructions, you will need to use Gail to climb up a wall to find a restroom. Atop the first platform, go to the left, behind the green wall to find the gold page.
5: Just above the entrance to the area where you hop out of the elevator shaft, you’ll need to use Batman. Grapple the gold lever and climb up to the small room where the gold page is waiting.