There are a few steps to follow to get rid of house gnats.
Find the source of the house gnats-You need to find the source of the house gnats. Most commonly they are found near sitting water, indoor plants, or in the kitchen and bathroom.
Destroy them with a vengeance-Destroying house gnats isn't an easy task, it takes skill and a strong will for extermination. The method I'll be going over includes only thrifty household ingredients. All you will need is a spray bottle, dish soap, water and/or baking soda and vinegar. You just need to use a few drops of dish soap and a table spoon of vinegar for each cup of water. With this these destructive gnats will parish with just a few spritz of your new chemical weapon. The best part is that you don't have to worry about this solution harming your indoor plants.
Gnat Prevention Program-So you've killed the pesky creatures, but what now? Follow these easy steps for gnat prevention:
If you have fruit, don’t leave it where the gnats can easily get to it.
Make sure you rinse your dishes before you leave them in the sink
Don’t overwater your indoor plants
Make sure that you soak up any standing water around your home
Now you know how to get rid of the gnats and how to prevent them, just keep it up! If they don't all parish the first go around, try again in a day or so, but don't wait too long or they'll multiply and overrun your household.