Hello, how would a person go about transferring to flat paper pattern the extra fabric contained in the princess seamed muslin alteration to fit the rounded abdomen. See photo. This design does not have a shoulder or armscye to slash up to and am concerned about retaining original lines so the pieces will sew together smoothly. The added amount looks almost like a double ended dart (opened instead of closed) to add the needed space; the widest spot is 5/8″ which should be divided between the two pattern pieces. Lower down it is 1/4″ which would be divided in half – 1/8″ for each piece. Should the original pattern cutting line be what is added onto? Or should there be some type of slash/spread? If so, suggestions how?