Put an old item on your front lawn as if it were free, then when someone tries to take it run outside and accuse them of stealing.
In a store, follow somebody. When they put an item in their cart, put it in yours.When they realize, say twinning,and run off.
Go to a drive-through and explain an item that you want without telling the person on the speaker what it is, when they say what your item is, tell them "no, it's not that" then keep explaining the same item and say the same thing and see what reactions people get.
Take the first item on your left, put a leash on it and take it on a walk through your neighborhood.
Walk up to someone, look at them closely, then mutter into an item of clothing, "Suspect clear".
Sorry, nothing left to see here at the moment.
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