Sheer fabric is thin and you need to add some body it by interfacing - especially in facings, collars, cuffs hems . When you have to interface a sheer fabric, you will have to do it with the fabric itself, as any other fabric used as interfacing will show through.So when you buy sheer to sew something calculate this as well.Other sheeres that can be used as interfacing are flesh coloured nylon tricot, organdy, organza, china silk, voile or tulle. In some cases a fusible knit interfacing which is sheer can be used.This will offer just the right amount of support but retains the beautiful drape of a fabric.