At 1:36, instead of pressing E to extrude then deleting the unneeded faces, just press Alt E then choose Extrude Manifold so that it doesn't create the unneeded faces.
Hi ttoffieplay ,
That's cool tip, but if you followed along and Deleted the top and bottom Faces (~0:48), this doesn't work.
If, you would instead have Hidden the top and Bottom Faces (with H), the Extrude Manifold does work as you describe:
Deleted Faces:
vs. Hidden Faces:
⚠️ It will make a difference, later in the Course, whether you have Deleted, or Hidden the top and bottom Faces, so be careful.