Player 1: As soon as you enter the main test chamber, look to your left and set your first portal on the wall where the excursion funnel leads. Now look where the Arial Faith Plate on the ground is located and turn around and look up. You should notice a row of shoot-able wall tiles, place your exit portal up here so when you now step on the Faith Plate, you’ll land in the funnel as it carries you across the chasm.
Player 2: Jump onto the Faith Plate immediately after player 1 and fire your first portal at the wall where the funnel you’re in finishes and then look up and to the left for a wall covered in rectangular wall panels. Aim your shot so the excursion funnel continues towards the ledge located above you.
Player 1: Drop off onto the ledge and once player 2 has safely joined you up here, switch the location of the excursion funnel to the left of the wall (so it’s passing directly under the item chute that’s located on the ceiling). Go ahead and press the red button now and a Displacement Cube will fall into the funnel and get carried right towards you both. Player 2: Set a portal on the rectangular wall panel located up here (where the red laser beam is), position the Displacement Cube so teh laser beam is directed directly at the middle of the wall and you now need to wait for player 1 to finish getting across the chamber.
Player 1: Drop down to the Arial Faith Plate below and when you land on the other side, look up and to your right for a rectangular section of wall panels. You want to fire off a portal so the funnel is now passing near the right-hand wall. Hit the Arial Faith Plate nearby (sending you back across the gap), and then simply drop down into the funnel below until you reach the exit at the other side.
Player 2: You just need to follow player 1 and make your way across to the exit via the excursion funnel. Now, once you reach the exit, look for the square wall panel to your right and set an exit portal here, so the laser beam is passing through to the beam receiver on the wall, raising the stairs that will lead you both to the exit!