Lay the fur fabric down with the cut edge running down the center top. This will be the opening front of your vest.
Put a shirt on top that matches the size of the child you wish to make the vest for. You can also try placing the child on top, but then you will have a much more wiggly template.
Cut out a neckline about an inch higher than the neckline of the shirt as well as cutting the bottom hem length several inches longer than the shirt (tunic length).
Mark an approximate of how wide the sleeves should be, and cut down the sides to that mark.
With your sewing machine and a mask to keep yourself from gagging on all the excess fur flying around, zig zag stitch along the cut armhole edge and the open front edges.
With right sides together, sew across the top shoulders, and finish with a zig zag stitch.
There you have it, a Viking Vest suitable for the most discriminating of Icelandic Jedi.