This bag might be just what you need. This bag is relatively small, has a zipper closure to keep things in (and maybe other things out), and has a wrist strap which makes it easy to 'fasten' to your body.
2 – 7” x 9 ” fabric pieces for exterior
2 – 7” x 9” fabric pieces for lining
1 – 2” x 12 1/2” fabric piece for strap
2 – 7” x 9” pieces of fusible fleece
2 – 7” x 9” pieces of fusible interfacing
1 – 9” or longer nylon tooth zipper
1. Fold the 2” x 12 1/2” fabric piece in half lengthwise, wrong sides together. Press to form a crease.
2. Unfold, and fold the long edges toward the center crease. Press.
3. Refold at the center crease and press.
2. Mark a 1” square at each end of the bottom edge of the exterior and lining pieces and cut out.
Inserting the zipper:
1. Stack the fabric and zipper in the following order:
2. Pin all three layers together. Using a zipper foot, sew the pinned layers together.
3. Press the fabric away from the zipper.
4. Repeat the process with the other lining and exterior fabric pieces.
5. IMPORTANT CHECK: with the assembly lying flat, the corresponding edges of the fabric should be in line with each other. Place a straight edge (ruler) along the edges to check this. If the edges do not line up or if either edge forms a 'V' shape with the ruler, correct the problem before proceeding.
3. Match up the exterior fabric pieces to each other with right sides together. Pin sides and bottom of exterior fabric.
4. Match up the lining fabric pieces to each other with right sides together. The teeth of the zipper should be towards the lining fabric. Pin sides and bottom of lining fabric, leaving an opening at the bottom of the lining fabric large enough through which you can turn the bag right side out.
6. For each corner cutout - open the bottom corner and match up the bottom and side seams.
Sew the opening closed.
7. Pull the bag right side out through the opening in the lining.