first you take a piece 4 times the size of your ipod and 1 cm extra on each side.
Turn it to the side you won't see on the outside and sew 1 side.
Sew the top like the picture and than the other side.
Reverse it, so the stitching is on the inside. Than sew the rest, like you can see in the picture. Firts one side.
Sew the other side and than the top.
Sew it like on this picture
You can make hooks on it like i did, or buttons
Here is the result. You can decorate it if you like :)