To create a ghost with a bodily shape, begin by making a frame for the underside of the ghost. Start by straightening the hook of a wire hanger so it stands straight up. Poke a large styrofoam ball through the pointed top of the hanger; secure with glue or tape if necessary. The size of the foam ball will determine how large your ghost is. To make a ghost that looks like ours, this is all you need to do for the frame.
To create a spooky ghost with a more realistic bodily shape, add foam tubing to the hanger to five your ghost arms. Wrap the center of a piece of clothesline wire six times around the padded area of a wire hanger so that an equal length of the wire extends beyond each of the hanger's ends. These ends should be longer than the length you want the arms to be. Slide a piece of thick foam tubing up each end of the wire and onto the padded area of the hanger. Use packing tape to connect and secure the tubes at the center of the hanger.
When the ghost frame is done, cover it in fabric. You can use upcycled or purchased white fabric, or up the spook factor by dressing your ghosts in old dress material. Arrange the fabric or recycled dresses on the assembled ghost frame by draping it over the foam or head and securing with hot glue. Shred and tear the draped fabric with a scissors, cutting off some pieces of the fabric for a spooky look, or leave the material as-is for a collection of friendly ghosts. If you made ghosts with arms, cover the ghost's head with plain fabric, then use the foam tubing to fill out the arms of the dress.
To hang the ghosts, insert screw eyes, hooks, or pushpins into the underside of your house's gutters or the ceiling of your porch. Use fishing line to suspend the ghosts, using extra lengths of fishing line or clear thread to hold them in place if necessary. For large or heavy ghosts, suspend the form with fishing line secured at the back of the neck, then attach an extra line to each side of the neck and hang from the same hook for added support.