Do you want to be a S.P.E.W. supporter like Hermione? Well first you need a badge!!
First, download this parchment paper and put it on a document.
Then add an oval shape.
Now put a text box inside the oval and write:
S.P.E.W.: The Society for the Promotion of Elfish Welfare.
Then print out your badge.
Finally cut it out and tape the pin onto the back of the badge. Ta-Da!!!