I made this one out of some left-over paper. The contrasting color shows the construction better.
The paper is ordinary copier/printer paper, nothing fancy or expensive. Astro-brights in 24-pound work the best, but even 20-pound is fine. A box-with-lid requires two sheets of paper: four squares each for top and bottom. Standard U.S. size 8 1/2 x 11 cut into 4 1/4 x 4 1/4 inch squares yields a box approximately 2 inches square by 1 inch deep.
This is a very simple "modular" box, meaning it's made of assembled pieces rather than being folded out of one piece of paper. But there is no glue or other binding used.
Video tutorial is here -- BUT . . .
I do mine slightly differently, but this video gives the basics.
Instead of turning the paper over for the third fold, I fold everything into the center on the same side. You'll notice that when they begin to assemble the four modules, the corner fold has to be adjusted. If you fold from the same side, that adjustment isn't necessary.
Also, I assemble the first three modules all the way in rather than holding them out to slide everything together at the end. It seems to be easier to adjust the last two modules rather than slide all of them at the same time.
Because the modules are flexible, top and bottom are made from the same size paper. The top just slides slightly open to accommodate.
I bought some 12" x 12" scrapbooking cardstock when it was on sale at JoAnn's and cut it into 6" squares for slightly larger, sturdier boxes, too.
All can be embellished with glitter or paint or rubber stamps or whatever.
One of these days I'm going to learn how to do some of the other boxes, but I never seem to have time. I have to keep making more of these for the jewelry I make!