Inserting a decorative inset into pocket flaps, collars and cuffs adds a designer touch to a garment which is further enhanced by piping the edges. Here we provide the step-by-step techniques.


  • Use general purpose sewing thread for seaming and piping and specialist embroidery threads for the decorative stitching.
  • Thread machine and bobbin with general purpose thread (although top thread changes for decorative stitching, keep same general purpose thread in bobbin).
  • Use a Tearaway stabiliser behind the decorative stitching to prevent the fabric puckering. Tear away excess stabiliser once stitching is complete.
  • Narrow piping cord works well with dressmaking, particularly when trimming collars, cuffs etc. This is wrapped with bias cut strips of fabric. Cut strips 2.5 cm wide (to take narrow piping and allow 1 cm (3/8”) seam allowance). This is the usual seam allowance for pocket flaps, as it makes sewing curves much easier!
  • You will need a zipper or piping foot for piping.

Remember to press as you go during each stage of the process.

Project 1 – Pocket flap




Upper Flap WS, Inset and Lower Flap WS

  • Cut out an upper pocket flap following paper pattern. Then cut this in half across the middle.
  • Cut a contrasting coloured inset piece the same width as the pocket flap x 2.5 cm (1”) wide.
  • Using general purpose thread and taking 6 mm (1/4”) seams join the inset to both new sections of the pocket flap (diagram 1).
  • Press seams, flat to embed the seam, then press open.
  • Place stabiliser behind the inset strip; work a decorative stitch of your choice down the middle using embroidery thread.


Try out different decorative stitches on a scrap of same fabric (with stabiliser) to see which you prefer. Check they will work around curves well if intending to use same stitches on curved collar or cuffs.



Piping edges ‘crowded’ at corner

  • Change to zipper or piping foot and general purpose thread. Wrap bias strip round piping cord, keeping edges even. Sew close to piping cord.
  • Place piping along curved edge of pocket flap keeping all edges even. ‘Crowd’ the seam which means sew as close as possible to the edge of the piping cord, easing around curves (diagram 2).
  • Place the piped flap, right sides together on flap facing. Pin in place.
  • Sew again, as close as possible to piping, slightly inside previous stitching to ‘crowd’ the stitch. This is so that all stitches will be hidden when complete.
  • Trim and grade the seams so that each layer is progressively narrower to reduce bulk. Notch the outer curves where necessary.


I use a pinking cutter or scissors to trim seam allowances as they automatically notch as they cut.

Turn through to right side. Press flap. Sew across top of open flap, keeping layers smooth and flat.
Your pocket flap is ready to apply to the garment.

Project 2 – Collar Inset

Now you are familiar with piping and straight edge insets, we will progress to curved insets!

Preparing the top collar

You will need tracing paper and tracing wheel to transfer markings to fabric and different coloured pens to mark pattern tissue paper with inset sizing.



It is important to use either metric or imperial measurements and not to mix the two, as absolute accuracy is essential to the success of this project.

  • The first step is to cut out collar section, following paper pattern. Then prepare the collar by interlining with a lightweight fusible such as Vilene G785. Next, draw a line on the pattern piece 4 cm (1 5/8”) in from the outer edge following the collar shape. Lay the pattern back on top of the right side of the collar. Place carbon paper face up underneath collar. Trace line onto wrong side.
  • Now return to the collar pattern. Draw another line 12 mm (1/2”) from the first on either side, using a different coloured pen. Draw extra balance marks before tracing, which are 3 mm (1/8”) snips on the pattern. These will help to match the curves when sewing together later. Trace off this new pattern, which should be 24 mm (1”) wide.
  • Cut apart interfaced collar on traced line. The outer collar band should measure 4 cm (1 1/8”). Make sure that the balance marks are snipped no more than 3 mm (1/8”) as 6mm (1/4”) seams will be used to sew the pieces together as in diagram 3.
  • Using the new pattern for the insert, cut contrast fabric on the straight grain. Do not interface unless fabric is very lightweight or unstable.
  • Starting at mid points, pin the outer edge of the insert to the inner edge of the outer band right sides together matching balance marks. Work with the convex (inner) curve on top each time. It is easier to manipulate the fabric this way. Sew an accurate 6mm (1/4”) seam. Sew the inner collar in the same way.
  • Now that the three sections are sewn together press both seams, flat to embed the stitch, open to ensure a smooth seam and then in toward the insert. The inner edges of the collar seam should butt together without any gaps and the collar should be the same size and shape as the original. Lay pattern back to check and adjust if necessary.
  • Cut a 12 mm (½”) wide bias strip of fusible interfacing. Fuse on top of butted edges of seam allowances. This prevents stretch on vulnerable sections and keeps the 12 mm (1/2”) wide band consistent.
  • Embroider inset with a suitable choice of decorative stitch. Test out first to check the effect along curves!
  • Press embroidered collar before applying piping.
  • Follow instructions for pocket flap above to apply piping and under collar. Diagrams 5 & 6

How it works

The 6 mm (1/4”) seam allowances, together with the 24 mm (1”) wide insert mean that the original collar pattern can be used without having to add seam allowances.

The collar is simply cut in two along the drawn line. It will remain the same size because the insert cut is equal in width to the total amount of seam allowances needed to sew the pieces together.

For example, four 6 mm (1/4”) seam allowances were needed to connect the pieces, 24 mm (1”) in total, so as long as the insert was cut to 24 mm (1”) the collar would fit back together like a jigsaw. In simple terms we put back what had been removed!

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