From Gakushu Youchien magazine.

Print the first image on a piece of paper, then turn that paper over and print the second image on the back side. If the alignment doesn't work and you can't adjust it, just print on 2 seperate papers and glue them together. If you are going to glue 2 papers together, color the pictures before you glue them. After coloring, cut along the dotted lines. Fold the different sections to change Sally's outfit combinations (diagram below).