After that I sewed two more on either side so my fabric looks like a plus sign.
Then sew each of the outer squares to its neighbor and you have a very floppy box. Do the whole thing twice and you have a box and a lining. In order to make the box stiff I then cut out another million squares, this time out of cardboard. I made each of these about an inch smaller than the fabric pieces, so about 10 1/2" by 10 1/2". Place one cardboard square into the bottom of your outer box.
Then put your lining, inside out, into the outer box.
Now slide a square of cardboard into all four sides of your box between the lining and the outer fabric.
Fold the outer and inner box fabric towards the cardboard, pin and sew it closed.
You can see that the box is no longer floppy, but the fabric is still a little too loose, so I used a needle and thread to sew a couple of knots through both layers of fabric in all four corners.
The boxes aren't perfect, but they hold clothes and fit perfectly in Sofia's shelves. Here's the first one in:
See how the clothing in the shelves without bins are spilling all over the floor? Look how much better it looks when all of the clothing is in a bin:
The best part of these bins, each side is a different fabric, so you can change the look just by spinning the boxes around.
And each box also has one side that is the same fabric, Sofia's favorite patchwork fabric:
Now, maybe, Sofia will keep all of her clothing put away! Yay free bins!