Decorative one, in this case.
I sewed a narrow rectangle around each mark. The buttonholes are quite long.
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I cut each one (not the stitches). Then I embroidered each one with overcast stitch.
And what cotton did I use? These are threads I pulled out of the fabric!
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I marked the buttons opposite to the buttonholes and sewed each one on.
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The completed costume.
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