What you need:
Draw a ghost shape on the construction paper with chalk or a black marker. Make sure to leave holes for the eyes and mouth.
Scrunch up the tissue paper (individual pieces) and glue onto the ghost shape, leaving the eyes and mouth holes empty.
You've got a scary (or friendly!) ghost for Hallowe'en!
If you've got white paper handy, you can make a mosaic ghost at the same time!