Cut out a tapered shape about 2 inches shorter than your wrist to elbow measurement.
Cut out another shape from fur, at least 1 inch
bigger in every dimension.
Lay the smaller piece face up on top of the wrong side of the larger piece.
Fold over each edge and stitch down. You may need to remove some of the overlapping fur at the corners to prevent them from becoming huge.
You'll end up with something like this. Fur goes on the inside against your skin. Cosy.
Make 6 equidistant holes along each side of the bracers and lace up with leather thonging.