You didn't say what grade level you teach, but with younger children, I had each child draw his/her face on a paper plate-added hair, glasses, etc., then had hand cutouts with a tissue crumbled up a bit to make it look like it was covering a sneeze over the mouth/nose area. Title was: "Cover your sneeze please!" I also did the germ spreading using cornstarch powder (messy, but easier to clean than glitter) I squeezed the box of powder to show a sneeze without covering mouth (Let it spray out), then covered the sneeze and "caught" the sneeze with my hand. I then proceeded to shake hands with each child, or tough their face or shirt-leaving "powder germs".
Oh, then I "Sneezed with powder into my hand and washed my hands and touched them leaving no germs behind. It was a great visual that they remembered.