Place your humidifier on a flat surface 1 foot away from any walls or heaters.
Remove the water tank and flip it upside down to reveal the cap. Open the cap and fill the water tank with cold water. Replace the cap and turn the tank over again to reinsert it in the humidifier.
Remove the medicine cup from the humidifier and fill it with your Vicks medicine. You can fill it all the way to the top, but don't add so much it overflows. Return the medicine cup to the cooling chamber.
Plug the humidifier in to the nearest outlet and turn the switch to "On." You can choose either the low setting or the high setting. A light will come on indicating that the humidifier is heating up.
Turn the humidifier off once you run out of water. Unplug immediately, but wait 15 minutes before moving the unit or cleaning it.