First the zipper - I bought a bundle of 100 zippers for $15.00. Yes, I should never have to buy another zipper! I liked these zippers because of the length and the pull. A longer zipper is important key in making this pouch easier to construct.
First, the size. I wanted to make a pouch for my knitting.
Sandwich the zipper between the outside fabric and the lining. TIP - always start with the top of the zipper. This is where a long zipper is helpful because you can open the zipper up and never have to worry about dealing with the zipper pull when you sew.
After sewing the zipper, flip both the lining and outside fabric so wrong sides are together, press away from the zipper and top stitch thru all the layers.
Now close the zipper so you make sure you have it in the right position and layer the other piece of lining and outside fabric with the zipper in the middle. Make sure you start at the top of the zipper. The position of the fabric will be the opposite, but you want to sew the zipper in the same direction. Press back the fabric, topstitch, and it should look like this
Close the zipper, layer the two halves with the outside fabric together and sew the long seam which will be at the bottom.
Open up the zipper and press that bottom seam open. Use some kind of a decorative or a zig zag stitch to sew that seam down thru all layers. With the seam sewn down it makes the bag a lot neater on the inside. Sometimes I have to trim the seam a bit before I sew it down to even up the layers.
Close the zipper and starting at the bottom of the zipper side of the bag, fold the bag so that the zipper is lined up with the bottom seam. I put a pin on each side of the zipper to hold the layers together.
Mark for the corners that will be cut away to make the pouch a box. I mark the corner 1 1/2" from the raw edge and 1 3/8" from the folded edge because you have to allow a bit for the fold.
Sew the seam between the corner marks. I sew the seam twice because I want to make sure this bag never comes apart.
Put your machine on a wide zig zag and tack across the zipper so you can cut the zipper off. Also cut out the corners.
Fold the corners and stitch. Don't freak out if the corners dont' line up exactly. Just even out the fabric side to side, stitch it, and trim. I didn't zig zag the raw edges since they are on the bias, but you could if you want.
Open the zipper up and lets do the other end. FIRST, make a handle! I cut a piece of fabric 4" wide and longer than I thought I needed - about 9" for this bag. press on some interfacing, fold the piece in half lengthwise, fold the sides to the middle, press and stitch on each side.
I forgot to take any pictures of this, but it is a simple handle.
With the zipper open, pin the zipper on each side with the bottom seam lined up under it.
Mark the corners just like you did before.
Sew the seam between the corner just like you did before.
Fold the corner and stick in the handle between the layers and sew. Just make sure the handle doesn't get twisted when you layer it in the other corner.
Your done! Turn the bag right side out. I did stuff a hand towel in the bag one end at a time and pressed the seams a bit.
Let me know if you have any questions!