What you need:
- green knit fabric (I had some sitting in my closet from a yard sale, the amount you need will depend on the size of the child... or adult)
- a shirt to use as a size template
- Small amount of dark green knit fabric for the hat trim (I cut up an old tshirt)
- brown fabric for the belt (I used leftover corduroy, but just about anything would work)
- yellow felt for the belt buckle
To make the top, I folded a piece of light green knit fabric in half and laid one of his shirts on top to to use as a pattern. I cut the costume a couple inches larger so he'll be able to use it for a few years, and cut the sleeves to be a tank-style top. I also cut it several inches longer than his t-shirt (since Toon Link's shirt is a little long) but... it might be a little too long. Oops. I'd go a little shorter than this next time. Use the first piece as a pattern to cut a second piece for the back.
On the front piece I cut the neck down a little more into a V. Then I laid a belt section on top of each shirt piece and lined them up at the same height. Cut strips of brown about 3" wide. If it's a woven fabric (I made the belt with left over brown corduroy), fold the raw edges under about 1/4" and press them to keep them in place. If it's a knit, you don't need to worry about fraying and can just set it in place without folding the edges under.