Step 6: Chain stitching and adding to your rows
Because you don't have to back stitch, you can save time and thread by "chain stitching" your quilt squares together. This means that as you sew 2 squares together, just after the end of the set of squares passes the needle of your machine, instead of cutting the thread, feed in the next stack of squares and continue sewing. See photos below to understand how this should look.
You will end up with a little chain of squares coming out the back of your machine all connected by thread. Now snip apart (being sure to keep them in order) and lay them out again on your work surface.
Next add square 3 to the first row (made up of square 1 sewed to square 2). You can see in the fourth photo below how I arranged the 2 square sets and flipped squares 3, 7, 11, 15 and 19 over onto the patches. I stacked them in order and set them next to the machine so I could chain stitch them and keep them in order.