Go on the Unstationary Scaffold. Place a portal on the wall where you are going and the other on the ceiling above the ledge.
Pass through the portal. Now, crouch and look at the next part of the room. Fire a portal on the wallpanel marked with a two dots sign.
When the Unstationary Scaffold has arrived at the end, place the other portal under you and go through it.
Look up and shoot the same portal as the previous through the pipe. If the Unstationary Scaffold has already restarted the move, place the other portal on a wall just above the Goo and pass through it.
Put a portal through the long pipe. When the moving panel is extended, enter in the den and place the other portal here.
Quickly after going through the portal, place a portal under each Turret.
Fire a portal right facing the High Energy Pellet Catcher and the other through the pipe on the floor, then pass through the portal.
Place the same portal as the previous where the pellet is bouncing, then wait for it to reach the catcher.
Wait for the Unstationary Scaffold to come back at the chamber entrance if necessary, then go onto.
Look up, then put a portal the pipe on the ceiling and the other on the wall where you are going.
Pass through the portal. Shoot a portal through the pipe on the wall and the other on the white floor.
Grab the Weighted Storage Cube, go through the portal, knock over the turrets and go down.
Place a portal through the pipe and the other near you. Quickly, pass through the portal with the cube and go on the middle of the grating.
Quickly, shoot the same portal as the previous under the grating, move to the portal to throw the cube on the button and come back on the middle of the grating.
Do the reverse path using portals, until you reach the Switch. Prepare yourself for the timed puzzle.
Press the Switch and go back on the middle of the grating at the final room. Place a portal on the white panel facing the exit and the other portal near you.
Jump just after passing through the portal to reach the exit.