Chamber 2

Once you drop down into the water, turn right and follow the water until you reach the Portal gun.

Fire off a blue portal at the white wall (with the Janitors art deco) and jump through to land on the platform above.

Make your way up the stairs and follow the only path possible until you drop down a ledge. Look to your left and you should spot an orange portal generating in the distance.

Turn to your left and fire off a blue portal at the wall, allowing you to pass over the gap with ease.

Once you exit the portal, turn left and you should spot the exit door. Fire off a portal to the wall beside the exit and step back through the orange portal to reappear by the exit.