Variation 1: Henley Placket
Following the manufacturer’s instructions, apply fusible interfacing to the wrong side of the two placket pieces. Transfer all markings to the front neckline for the placket.
TIP: Before stitching the placket, baste around the rectangle marking at the center front using a straight stitch. This can help you get perfectly straight lines and corners when sewing the placket in later steps.
Match the two placket pieces to the center front at the markings.
Match the right sides of the placket pieces to the wrong side of the front.
Using a straight stitch, sew the placket pieces to the front. Start at the neckline and stitch down to the bottom edge of the front rectangle marking. 
Press the long edges of each placket piece to the wrong side at 1/2" (1.25 cm). Cut the front fabric onlyalong the centerline. Cut from the neckline to the tip of the triangle marking. Clip from the tip of the triangle at an angle to the end of each placket stitch line, creating a short triangle flap. Be very careful to not clip the placket fabric, or clip past the placket stitch lines
TIP: Clip a taller triangle piece than what is marked by cutting down the center front to about 3/4" (1.9 cm) before the placket stitch lines. Making a taller triangle piece can be helpful when folding this piece in later steps, especially if you are using a lightweight knit
Fold the placket pieces in half, sandwiching the seam allowances.
Push the bottom edges of the placket to the right side of the front through the opening.
Lay the front right side facing up, and position the placket pieces so that the right placket is overlapping the left placket. The placket pieces should overlap each other evenly at 1" (2.5 cm). Re-press the placket pieces if needed so they overlap evenly.
Using a needle and thread, baste the placket pieces in place. Using a slip stitch, sew the folded outer edges of each placket to the stitch lines.
Topstitch along the basted edges of each placket stopping just before the end of the placket stitch line.
Tidy up the bottom of the placket pieces. Clip the bottom edge of the left placket piece to about 3/8" (1 cm). Fold under the bottom edge of the right placket piece so no raw edges are exposed. Press.
Using a needle and thread, slip stitch the bottom edge of the front opening (the top of the triangle cut out) to the placket.
Using a needle and thread, stitch the bottom of the right placket in place, securing it to the front.
On the right side bottom of the placket, use a straight stitch to stitch a square and decorative “X” to reinforce the placket.
May 17, 2022 — Morgan and Matthew Meredith