Photographed late at night with a flash... but finally, here it is: Envelope Style Mini-Backpack with Elasticized Straps (or is it a doll carrier...ours does double duty).
This backpack is made by forming two ``pillowcases`` and sewing them together.
Cut four 10 inch by 12 inch squares - two from lining fabric (I used cordouroy) and two from outer fabric (I used upholstery cotton). These form the front and back.
Cut two 4 inch by 16 inch rectangles to make straps.
Using the large pieces, place the good side of one lining fabric against the good side of one outer fabric and sew up three sides, leaving one short side open like a pillowcase. Turn right side out and press with iron. Do this twice so you have made one front of the backpack and one back.
Here is how it looks turned right side out.
Go make yourself a swell pocket and attach it to one of the outer fabric sides. This is your backpack`s front. Set it aside.
To make the straps, fold each rectangle in half, stitch up the long side only (leave the top and bottom open) and turn right side out. Press the seam to the middle.
Cut two 10 inch pieces of elastic. Using a safety pin, thread the elastic through the strap. Stitch across the bottom once the elastic is in your fabric to keep it from slipping all the way through. See how the fabric will start to gather up on the elastic - now stitch the top of the elastic in place too. Zigzag the top and bottom raw edges.
You will now have two of these.
Attach the straps to the outer side of your back panel. Fold each zigzagged edge under and stitch on. I positioned mine very close to the top of the backpack, and left about 2.5 inches at the (unfinished) bottom.
You now have a finished front and a finished back, both with open bottoms.
With the good sides together, lay the front over the back. The pocket and the straps will be facing each other. Sew the two sides closed. Next, sew the bottom closed then trim and zigzag the raw edge.
Turn your backpack right side out. You now have an envelope-style backpack. You can add a button or velcro closure if you desire.