1. Fold each fabric square in half, right sides together. Stitch 1/4" from each end.
2. Open the edges of the folded square and refold, matching seam lines. Pin and then stitch from each corner to about 1" of the seam at the center, leaving a small opening through which you will be turning the square inside out.
3. To reduce the bulk, trim the corners and press the seams open. Use the tip of your iron for this, trying not to press any creases in the outer edges of your folded square.
4. Turn the square inside out through opening and press. Close the opening with a few tiny stitches. At this point you have completed the first fold for your background square.
(Please note that this step and the following ones refer to the traditional way of sewing this block. For a faster variation please refer to the tutorial on A Modern Approach.
5. Bring each corner to the center in turn, keeping the outside corners as sharp as possible.
6. Stitch the center down through all layers and fasten off at the back of the square. The stitches should form a tiny cross at the back. Repeat the stitches several times to keep the four corners held tightly in the center.
With this step we have completed the second fold of our background square, which should now measure the finished size we wanted. The first background square is now complete!