Singer XL-420 Manuel D'instructions page 56

6. Place the fabric under the foot. Pull out the bobbin thread
underneath the fabric to a length of about 4 inches to the rear.
the buttonhole foot, and then lower the buttonhole foot.
8. While holding the top thread, start the machine.
* Sewing will be completed automatically in the following order.
up the fabric in the center of the buttonhole.
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1 2 3 4 5 6
Buttonhole foot alignment position
Position d'alignement du pied boutonnière
Posición de alineación del pie de ojaladora
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