Singer 7467 Confidence Manual page 70

CORDED BUTTONHOLES
Hook filler cord (crochet thread or buttonhole twist) over the
spur and pull both ends of the cord forward under the foot and
tie off the cord as shown in the illustration.
Sew buttonhole so that zigzag stitches cover the cord.
When completed, release the cord from foot and snip off extra
length.
0
Spur
Saliente
Tige