I am using DK (8ply) yarn and 4mm needles, but you can select other ones to create different size.

Step by Step video tutorials on making up:

How to Weave leftover yarn

How to Sew a Shank Button

How to Join the Top Decoration to the Main Body

How to Overlock stitch by Hand

How to Install Zipper to the fabric lining

How to Knit iCord for the Wrist Strap

Video tutorials updates
16/11/12: how to weave leftover yarn video uploaded
18/11/12: how to sew a shank button uploaded
20/11/12: how to sew the top decoration to the main body video uploaded
25/11/12: how to overlock stitch by hand
27/11/12: how to install zipper by hand
3/12/12: how to knit iCord for the wrist strap