Below is an example of slipstitching the squares together.
If you'd like to have an invisible join, use this method.
Back to work on our bags.
Lay out your squares in the following groupings.
There should be two groups of 6 squares, two pairs of 2 squares, and one group of 3 squares.
This will comprise the front panel of the bag.
This will be the bottom panel of the bag.
This will be the back panel of the bag.
This will be one of the side panels.
And this will be the other side panel.
As I said, join the squares using whatever method you like. Once the panels are assembled, then join them together. I just used a yarn needle to whipstitch it all together. Then, I continued to use the yarn needle to sew the straps on to the bag. I used the middle of the squares to mark my strap placement. VOILA!
You can leave your bag like this, but I will be sewing in a lining next week. Too many holes! I'll be dropping everything. :)