Now look up at the ceiling and you should notice a singular square wall panel situated right over the edge of the platform. Get a portal up here and then another one under the blue gel dispenser, press the button and the blue gel will create a handy launch pad for you.
Stand by the end of the orange propulsion gel and then run up it, you'll automatically bounce over to the platform directly ahead, hit the wall and come to a standstill on the walkway. Walk around to the back of the platform, lay a platform on the wall here and then on the wall directly above you.
Chapter 7 starts rather unexpectedly as you approach the force field that leads to the next test chamber (directly after Chapter 6 Chamber 8).
Line yourself up correctly before running towards the blue gel, bouncing through the two portals and using the velocity gained to send you flying right over to the exit.