Did it say to stitch in the ditch of the "shoulder seam" and the "underarm seam?" I assume that's what it means. Anyway, that's a way of tacking the facing to the inside of the garment so it won't keep popping out of the armhole when you're wearing it. If you don't want to stitch in the ditch, you can just hand tack it to the seam allowance on the shoulder and underarm with a needle & thread (that's probably more professional looking anyway).
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Did it say to stitch in the ditch of the "shoulder seam" and the "underarm seam?" I assume that's what it means. Anyway, that's a way of tacking the facing to the inside of the garment so it won't keep popping out of the armhole when you're wearing it. If you don't want to stitch in the ditch, you can just hand tack it to the seam allowance on the shoulder and underarm with a needle & thread (that's probably more professional looking anyway).
Diana Sewing Lessons
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Thanks! Now it makes more sense to me. Much appreciate your response.