Biscornu (offset square cushion)

Step 19 Sew on your buttons

Sew on your buttons. The thread should go from one button, pass all the way through the center of the biscornu, and then go thorough the other button. Keeping the thread between the buttons very taut is what creates the signature "dent" in the center of a biscornu. Creating this dent is another reason not to stuff your biscornu too firmly -- if there is too much stuffing, it won't dent easily (if at all), and you'll probably break many, many threads trying.