Here is a step-by-step guide for sewing a side seam pocket (sometimes also known as in-seam pocket). The steps are for garments with a waistband. It's based off this Maven Pattern tutorial, but much simplified.
Note: A 5/8″(1.5cm) seam allowance is used in this post.
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Step 0: Cut out the pocket bag pieces
- Use a pocket pattern that you already have, or simply draft one yourself.
- Make sure to add the curvy bit at the bottom to help with overlocking later on (a trick that I learned from the Maven Pattern tutorial).
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Step 1: Stitch along the garment side seams and overlock
- Align the pocket pieces to the garment side seams. Stitch into place (the dashed purple line in the photo below) with 3/8" seam allowance so that the pockets will sit slightly inside when finished.
- Overlock the entire garment side seams (the orange line in the photo below).
- Press open the pocket pieces.
- (Optional) Understitch the front piece 1/8" from the edge, if desired. This understitch will prevent pocket bag from rolling out to the front. I don't find this a problem most of the time except when using super soft/silky fabric.
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Step 3: Stitch the front and back pieces together
- Line up the front and back pieces along the garment side seams. Pin 1” from the top, and again 6” down, leaving a 5” gap as the pocket opening. NOTE: You can adjust the gap to suit your hand size.
- First, Stitch 1: From the top of the waist line stitch down to the 1” mark with a 5/8″ seam allowance. Reverse stitch to secure.
- Then, Stitch 2: With 5/8″ seam allowance start stitching from the edge of the pocket along the curve, up to the second pinned mark, pivot, then down along the entire garment side seam.
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Step 4: Overlock to finish
- Overlock the pocket starting from the edge, along the curve, and follow the curvy bit at the bottom towards the side seam.
- Press the pocket towards the front of the garment and this pocket is done! Repeat on the other pocket, or follow the rest of the garment instruction to finish.
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When completed, this is how the garment will look from the outside:
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