How to make elastic-waist pants

1. Materials & tools

Materials (child / adult M)

• Fabric (light–medium cotton, linen or knit) — about 110 cm wide × (rise + inseam + 15 cm) × 2
• Waist elastic (2–3 cm / 3/4–1 in wide) — the waist measurement

Tools

• Sewing machine (or needle and thread)
• Fabric marker or pencil
• Ruler and scissors
• Iron
• Pins or clips

2. Make the pattern (auto-generated in Katagami)

With the Katagami pattern tool, you just enter the finished size and it drafts a seam-allowance-included pattern, tiled to print at actual size on Letter or A4.

1. Open the tool
   Open the pattern tool and choose “Kids' clothes” → “Elastic-waist pants” from the tabs at the top.
2. Enter the size
   Enter the rise, inseam, waist and hip. Presets cover heights 80–130 cm and adult M.
3. Set the seam allowance
   Use the slider at the bottom (beginners: 1.0–1.5 cm / about 3/8–5/8 in).
4. Print
   Press “Print (actual size)”, then in the print dialog set Scale = 100% and turn “Fit to page” OFF. Check the 50 mm calibration box on the first guide sheet with a ruler.

3. Cutting the fabric

1. Trace the pattern
   Trace the cut line and seam line onto the wrong side of the fabric. Align the grain with the grainline.
2. Cut
   Using the same pattern for front and back, cut 2 of each (4 pieces). The right edge is the crotch curve (center-seam side).
3. Finish the edges
   Zigzag or serge the edges so they don't fray.

4. Sewing

4-1. Sew the center seams

1. Place the two front pieces right sides together and sew the crotch (center) curve.
2. Do the same with the two back pieces.

4-2. Sew the sides and inseam

1. Open the front and back out and place them right sides together.
2. Sew each side seam.
3. Sew the inseam in one pass, from one hem all the way to the other.

4-3. Make the elastic waist

1. Fold the waist under by the seam allowance, then again by the elastic width plus ease; stitch around, leaving an elastic opening.
2. Thread the elastic, fit it to the waist, sew the ends and close the opening.

4-4. Hem

1. Fold each leg hem under twice and topstitch.
2. Press to finish.

5. Tips & variations

• Shorts: shorten the inseam for shorts.
• Knit fabric: use a stretch/zigzag stitch for joggers.
• Pockets: add patch or in-seam pockets before closing the sides.