Time for action — adding the portals

This is the final touch, adding portals to the cabin. The cabin is not rectangular, so you will have to rotate the portals to match the angle of the walls:

1. Press Numpad 7 to get the Top view.

2. In the Viewport Shading menu on the 3D View header, select Wireframe shading.

3. Select the copy of the portal.

4. Press R, Z, 90, Enter.

5. Press G and use the mouse to move the portal next to the left side of the cabin. Press theLMB to release.

6. Use Ctrl+MMB and Shift+MMB to zoom in so you see the portal and the portal holes on the left side as well.

7. Press G and use the mouse to get the portal aligned up as closely as possible with the forward portal hole. Press theLMB to release.

8. Zoom into the forward portal hole. The portal window is a little larger than the portal hole. Aligning the dot that marks the center of the Portal Window with the outside wall of the cabin will help to get started. Then make sure that the sides of the portal window extend on either side of the portal...