How to make a phone crossbody pouch

1. Materials & tools

Materials (standard size)

• Main fabric (canvas, faux leather or heavy cotton) — about 50 × 40 cm (20 × 16 in)
• Lining fabric — the same amount
• Fusible interfacing — for the main fabric
• Webbing or a self-fabric strap — the length you chose
• Snap or magnetic fastener — 1 set
• Optional: a slider, swivel hook and D-rings

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 “Bags” → “Phone crossbody pouch” from the tabs at the top.
2. Enter the size
   Enter your phone's width, height and thickness, the flap depth, strap length and cut width. Presets cover standard, large-screen and slim.
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. Measure your phone
   Measure width, height and thickness with the case on. The camera bump counts.
2. Trace the pattern
   Trace the body (base on the fold), the flap and the strap.
3. Cut
   Cut the body in main and lining, the flap in main and lining, and one strap.

4. Sewing

4-1. Make the flap and strap

1. Sew the flap main and lining right sides together, leaving the attachment edge open. Clip any curve, turn and topstitch.
2. For a self-fabric strap, fold in quarters and topstitch both edges.

4-2. Sew the sides and gusset

1. Fold the body at the base, right sides together, and sew both sides.
2. Pinch each base corner into a triangle and sew across at the phone's thickness. It is a small measurement — use a ruler rather than eyeing it, and check both sides match.
3. Trim the triangles to 1 cm.

4-3. Attach the flap and strap

1. Turn the opening edge under twice and stitch.
2. Stitch the flap to the back of the opening with two rows, or a rectangle with a cross.
3. Stitch the strap ends at the sides. D-rings here let you change the strap later.
4. Try the strap on before sewing it down — length is much easier to judge on the body than on the table.

4-4. Add the fastening

1. Put the phone in, close the flap and mark where it lands.
2. A magnetic fastener opens one-handed, which matters on a bag you open while walking.

✏️ The thickness measurement is where this usually goes wrong. Measure with the case on, at the thickest point, camera bump included. Entering 1 cm when the reality is 1.5 cm produces a pouch the phone will not go into.

5. Tips & variations

• D-rings for a swappable strap: stitch D-rings to the bag and clip the strap on, and you can change it whenever you like.
• Add a slider: it lets you adjust for wearing over a coat.
• One inner pocket: on the lining, for a card or a key.