Cut out a collar template in whatever shape you want. Make sure to measure how big you want the collar to be.
Cut collar out of extra stiff pellon.
Cut out two of the collar in the fabric you want to use.
Sew collar with right sides of fabric together and pellon on back of one piece.
Trim seam on collar and turn right side out.
Top stitch along sides and top of collar, leaving bottom open.
Cut out 2 pieces of cape in whatever fabric you want. I just measured the length I wanted the cape and made my own shape.
Sew cape along sides and bottom with right sides of fabric together, leaving the top open.
Top stitch along sides and bottom of cape, leaving top open.
Attach back of collar and back of cape and sew together, leaving front edges of both open. It's kinda hard to see in the picture above, but I left the lining and inside of color unattached.
Fold up lining of cape and pin to collar. Sew along seam.
This is what cape should look like finished.
Attach hook and eye to cape for a closure.