Envelope Pillow Cases

My mom got me hooked on making these cute changeable pillowcases.  They are super easy to make.

One 17 inch square (front)

Two 17 x 11 inch rectangles (back)

Make a nice seam on the back pieces. (17 inch end). Now overlap back pieces to make a 17 inch square. Place right sides together on large square and serge outer edges together.