Using Threadbangers video, as a guideline, draft your pattern pieces. Cut them out, and make a mock-up to test your pattern. Once you finalize your design, cut the pieces out of leather for the outer layer and a gray fur for the lining. After getting the leather cut out, grab some waxed thread (can be found in the leather working section of your local Joann's store) and a needle with a really big eye. Hand sew a decorative 'x' stitch on the two crown seams. Make the lining.
The only thing that really deviates from the video is the pipecleaner structure inside the ear flaps to make them stick up. To do this, you make another ear flap piece out of just a cotton cloth as the interlining (it can be funky or ugly fabric since it won't be visible in the finished product). Take four pipecleaners and make two 'V' shapes out of them. Zigzag stitch them on the ear part to secure them to the interlining. Baste stitch this piece down to the seam allowance of the outer layer (leather). Once you finish that, continue on per the video's directions. Have fun!