There is something deeply unsettling about a group of pale, floating shapes swaying in the dark. A single ghost is a classic; a swarm is a nightmare. To create this effect, you’ll need cheesecloth, white fabric, or even old white bedsheets, a generous amount of liquid starch or white glue mixed with water, and invisible fishing line. Cut your fabric into large, ghost-like shapes with torn, irregular edges—perfectly smooth sheets look like laundry, not spirits. Dip each piece into the starch mixture, then wring it out and drape it over inflated balloons, foam balls, or even a cheap wire frame. Let it dry completely. Once the fabric hardens into a stiff, eerie shape, you can remove the ball or balloon and see your ghost.

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