Here are last year's paper pots ready for seeds and or transplants from seed trays.
The folded piece of paper in the third photo (below) is about 20 inches by 5 inches. There is water on the small plate. The can is a standard 15.5 ounce size. A larger can will, of course, make a larger paper pot.
I think Jamey does a pretty good job showing you how in these photos alone, but if you have any questions, leave a comment and we'll be sure to post an answer. Happy potting- spring is coming!