The video is not about creating cloth, but still, I found one very interesting piece of information, why cloth should be rectangle.
Alan Watts The importance of cloth (https://www.youtube.com/watch?v=uRnvZqHm1_s)
So it's not a tutorial by it means, but something we should keep in mind when creating 3d cloth :)
Almost forget, about the rectangle, it's minute 05:50