A continuous bound placket is one of my favourite methods for a sleeve placket where lightweight fabrics are used, such as on a blouse or dress. It is easily inserted into a one piece sleeve – not at the sleeve seam, but at the little finger where a vertical split is made.
You will need to cut the binding twice the length of the split, and a cut width of 25mm (1″) will give a finished width of 6mm. The binding should be cut on grain, not the bias.
Here I have laid the opened out sleeve split over top of the binding, with the right side of the binding to the wrong side of the sleeve. The raw edges align at either end of the split, but at the apex of the split they are offset by 5mm – this is how it will be sewn:
Stitch using a 6mm (1/4″) seam width towards the apex of the split…
…where you leave the needle down to reposition the fabric, and continue stitching to the other end.
It should look like this:
From the right side of the sleeve, turn the unattached long edge of the binding in 6mm, and fold it over again to just overlap your previous stitching. Edgestitch the binding down along its length.
If you are finding this a bit tricky – sew the first few stitches and stop with your needle down, then you can position your fabric again. Making the binding taut by pulling it slightly towards you helps to form an even binding width. Pull both top and bottom layers evenly so that the binding does not twist like a rope.
It is best not to press the edge down first, with a bit of practise you will actually achieve a neater result if it is pressed after you have edgestitched.
Fold the edgestitched binding in half, right sides of sleeve together, and backtack diagonally across the fold like so:
The finished binding will look like this:
The front side will be folded under as it is inserted into the cuff…
…and the back remains flat when it is inserted into the cuff:
Now all that is needed is to attach the cuff
, and sew the buttonhole and button. When the cuff is buttoned, the placket is practically invisible and looks just like a tuck in the fabric.