This version won't have the detail, so if you need more explanation, check out last week's link. As always, if you have any questions, leave me a comment and I'll try to help.
EASY Adjustable Waistband Tutorial
fabric for casing
ruler, cutter, thread, etc. (you know, the basic stuff)
button hole elastic (Found mine at Hancock's. You could use regular elastic, but you should put actual sewn buttonholes in it to keep it from unraveling.)