Homemade Wasp killer Take a plastic bottle & cut the neck off. Remove the cap,flip the neck upside down, and place the neck into the bottle. Tape and/or staple the top together. Bait the trap. The wasps should enter the trap completely in order to access the bait. Some bait ideas include: Meat - Dishwashing liquid and water Sugar and water Soda with a few drops of hand soap Hang it up outside. Empty the trap regularly. Be sure the wasps are dead before removing them.