How do I use the Pintuck Foot to create evenly spaced tucks?

Snap on the Pintuck Foot and insert a narrow twin needle (SINGER Style 2025), threading the machine with two spools of thread and increasing the top thread tension. Set the machine for a straight stitch, mark the first row of stitching with a marking tool, then align the marking with the center of the foot and stitch the first tuck. To stitch subsequent parallel tucks, position the first completed tuck into one of the grooves on the underside of the foot — the groove chosen determines the spacing between tucks. (Page 23)