To make it, mix 1 tablespoon of mint toothpaste with 1 tablespoon of baking soda. Slowly add 1 tablespoon of white vinegar, letting the mixture bubble. Stir in 120 ml of lukewarm water and a few drops of peppermint essential oil if you have it. That’s it—your bug-fighting potion is ready. Pour the mixture into small containers, like jar lids,...