Description:
Create portals, so you can reach the exit.

Instructions:
You can create two portals. Stepping into one will teleport you to the other.

Use the mouse to aim your portal gun, left click to shoot.
Press AWD to move around.
Press Q to launch a blue portal, E to launch a yellow portal.
R closes both portals.
Sometimes there are objects that you can pick up, press F to do this.