Tap the fluid #1 and fill the container with the yellow square.
Tap the fluid #2 and fill the container with the blue square.
Tap the film cartridge in your inventory and tap the developing device.
Tap the table,
Tap the safelight and insert in the lamp.
Tap the white sheet in your inventory and tap the wooden plank.
Tap the switch to get red light.
Tap the sheaf-binder.
Tap the sheet and move it in container with yellow square the move in the blue.
Tap to take the developed HINT (needed in bedroom).