This is a tutorial created by Youtuber SKM demonstrating how to make a functional Rubik's Cube out of cardboard using this template available for free download via Google Drive. It looks...rather complicated. And if you seriously are considering building a Rubik's Cube out of cardboard, please stop making me sad and just let me give you the $7 it costs to buy a real one on Amazon, I don't even care if you lie and spend it on booze instead but you do have to share if you do (I like those little bottled wine spritzers).
Keep going for the video.
Thanks again to my buddy hairless, who builds his own LEGO sets out of cardboard because times are tough and that plastic ain't cheap.