It may look a bit boring, but it's perfect as a library book bag or a grocery tote. It's self lining so it's heavy duty and super easy.
Start with one large square of fabric. Mine measures 31"x31". That's my bag. The handles are 3.5"x26". Feel free to make your handles longer. This pattern works with any size bag, so go ahead and make yours smaller or larger if you wish.
Fold the fabric square in half and sew the three sides. Leave a 4" gap on the long side to turn the bag. Keep that gap near one end or the other, not in the middle.
Now we're going to box the corners. Fold your corners so the seams meet in the middle. Measure 4" across and draw a line with a pencil.
Sew over your pencil line.
Turn your bag right side out. Now you have a big ol' rectangle with funny corners.
Take it and stuff one half down into the other half. Make sure to match the base in the seam and corners.
See the inside of the bag? You'll notice that my opening I used to turn the bag is on the inside. It just makes it nicer if my hand sewing is a bit imperfect.
Sew that gap closed by hand. Press the bag. You want a good crisp edge at the top. You can press the sides and create a nice crisp line from base to top as well.
For the handles, fold them in half lengthwise and sew the side seam. Turn the handles and press flat. Turn in the raw edges on the ends of the handles by about 1/4". Position at the top and sew down. Mine are spaced two inches in from the corners or about 4" from the side seam.
That's it. 30 minutes to a basic bag. It's ready for the grocery store or the library.