Lay the pillowcase out on a flat surface. We will refer to the open end of the pillowcase as the bottom and the closed end as the top.
Add black stripes, about 1” apart, to pillowcase using black electrical tape, overlapping tape at both top and bottom of the pillowcase. You should get about ten stripes.
Cut two triangles, about 4” long and 2” wide, from the black felt. Cut two thin strips from the felt, about 4” x 1/4”.
Fold down all the ends of the tape from the stripes.
Place the triangles, point side down, next to each other at the top center of the pillowcase. Lay the thin strips underneath the triangles, these will form the neckline and the triangles are the collar. The thin strips should come together in a point below the collar.
Carefully remove the section of tape that is running through the center of the neckline and trim with scissors.
Use the glue to attach the collar and neckline to the pillowcase.
Place the whistle necklace on the pillowcase, positioning it around the “neck”. Holding the necklace and the pillowcase, fold the top of the pillowcase over itself and tape the necklace string to the back of the pillowcase.
Carefully fit the pillowcase over the back of your chair.