How to make a rompers

1. Materials & tools

Materials (size 80 cm)

• Main fabric (jersey or interlock) — about 100 × 80 cm (39 × 31 in)
• Ballpoint machine needle and stretch thread
• Bias tape for the neckline and armholes — about 120 cm (47 in)
• Snap fasteners — 3 sets

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” → “Rompers” from the tabs at the top.
2. Enter the size
   Enter chest, length from shoulder to crotch, shoulder width, crotch tab width, neck width and ease. Presets cover 70–90 cm.
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 front and back, including the crotch tabs.
2. Cut
   Cut one front and one back. Cut knit lying flat and relaxed.
3. Finish the edges
   Knit does not fray, so edge finishing is optional.

4. Sewing

4-1. Shoulders and sides

1. Sew both shoulder seams with a stretch stitch.
2. Sew both side seams, leaving the crotch tabs unsewn.

4-2. Bind the neckline and armholes

1. Sew bias tape around the neckline, letting it follow the curve without pulling.
2. Bind both armholes the same way.

4-3. Finish the crotch and add snaps

1. Turn the edges of the crotch tabs under twice and stitch.
2. Fit three snaps where the front and back tabs overlap. Space them so you can open just the middle one for a quick nappy check.

✏️ Do not stretch bias tape as you sew it round the neckline — a pulled binding puckers the whole edge. Let it follow the curve at its own pace and feed it gently.

5. Tips & variations

• Soft fabric next to skin: jersey or double gauze. This sits directly against the baby all day.
• Two rows of snaps: nappy sizes change. A second row of snaps lets you lengthen the crotch later.
• Add sleeves: borrow the sleeve from the kids' T-shirt pattern and set it into the armhole.