first you want to decide how big you want your bag, i made mine with a 9in zipper so i cut my fabric 9in by 22in you can change this simply by changing the size of your zipper. just cut your fabric to the width of your zipper.

then you'll want to sew your zipper to the top of your fabric on the open ends. so you have a tube.

now you want to lay your project down flat with the zipper in the center wrong side out.

MAKE SURE YOU UNZIP YOUR ZIPPER HALF WAY OR YOU CANT TURN THIS OUT AGAIN.

and just sew up the sides.

now to get that swanky box look you want to fold the corners out so your seam is in the center.

hopefully your corners are even not all off like my drawing if you check the web sight i linked it has way better pics i took some but the kids erased them :/

then just sew strait down so your sides are a square.

and just cit of the triangles.
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