There are a few different ways you can use a humidifier. If your home is very dry and you need to add moisture to the air, you might want to consider using a humidifier at night. You can also use it in the morning or evening, but you will want to make sure that your air is dry first. This is very important, as it can save you a lot of money, not to mention stress and discomfort. Humidifiers are also great for people with asthma, allergies and other respiratory problems that can cause your air to dry. If you have a serious cold or the flu, you might want to consider a humidifier, as it will help with your congestion and sore throat.