Sew shoulder seams of both top & inner yokes (sometimes front & back yokes are connected together into one piece).
Sandwich back piece between yokes & sew back seam.
Fold yokes upwards & press neatly.
Roll the whole back piece & pin to keep out of the way.
Pin front pieces to top yokes (face to face) and then roll & pin front pieces to keep out the way.
Fold yokes downwards, sandwich rolled pieces between yokes. Then pin & sew front yoke seams.
Finally turn yokes to face releasing rolled pieces; flatten back & front pieces & press yokes seams neatly.