Essential oils diffused in the air will make you feel better emotionally, spiritually, and physically. Diffusers also help kill the germs in the air.
Dry inhalation is putting a few drops on a tissue and breathing it in. You can also just breath the scent from the bottle or put a drop or two on your shirt collar. You can put a few drops on you pillowcase, pajamas, or sheets at night.
Diffusers that use heat can change the chemical makeup of your essential oil. This may change the therapeutic qualities of the oil. A cold air diffuser uses room air to blow the essential oil into the air.
Put a cotton ball on your heating or cooling vent or a fan with a couple drops of essential oil on it for a cheap and easy way to scent your room.
Locket diffuser is a locket, necklace, or pendant that has a special place in it to add essential oil or combination of oils to gently scent the air you breath.
Aroma lamps are little lamps that you add water and oil to the dish area. As the water heats up, the scent of the essential oil is dispersed into the air. This looks nice, but you need to make sure you don't leave it and let it dry out or the dish may crack. It works okay in a small room.
Light bulb rings helps disperse the scent into the air. Place the ring on a cool light bulb, put essential oil in the groove of the ring and then turn on the light. Make sure you don't get essential oil on the light bulb or do it when the bulb is hot. This could make the bulb break. I never actually tried this, so i don't know how well it works.
Scentball diffusers are used by plugging them into any outlet in the house. They are easy to use and only take up a small amount of space. They use replaceable pads that are not very expensive. You can only use them for a couple of hours at a time. I have a couple of these, but seldom use them. I got spoiled by glass and fan diffusers. Maybe you would like them. It's a cheap way to try it.
Dashboard diffusers plug into the accessory power in your car. It freshens the car and depending on the kind of essential oil you use it can be either relaxing or energizing. It can help keep you more alert. This is great for long rides. Or perhaps you would want a relaxing scent to calm the little ones.
Clay figurine for essential oil is pretty useless in my opinion. They don't disperse the scent very well at all. I found a cotton ball worked better.
I have a small aroma shell diffuser on my desk where I do the bills. It plugs into a electric outlet and I put a few drops of lavender essential oil on a removable dish. The low heat sends the scent gently into the air. When I'm done I just need to wipe off the dish and shut off the switch. This is subtle but very delightful. I find it is just enough scent to relax me while I work.
Ultrasonic diffusers use high frequency vibrations to convert water and essential oil into billowing clouds of fragrant therapeutic vapor. It's said to be quiet and uses cold air mist. It works for up to 5 hours. I haven't tried this kind yet, but it looks very useful. I think that the extra moisture in the air would be very helpful in the dry winter air or a dry climate.
Ceramic night light diffusers with a area on top for the essential oil work fairly well. They are nice in a small room like the bathroom. These are easy to use and easy to clean.
Fan diffusers are both safe and pretty quiet. I used one all night with no problems. What I like about this kind of diffusor is you put the essential oil on a pad. This allows you to use thicker oils if you want. What I don't like about it is you need to replace the pad. How often you need to change the pad depends on how much you use it, or how thick the oil is and how much oil you use. The only cleaning is changing the pad and clean the fan part. This was easily done with a hair blower or air compressor. Overall I am pleased with fan diffusers.
Glass diffusers have a glass bottle that the essential oil is placed in. A glass diffuser is also called a nebulizer. These break down the droplets even smaller, letting the essential oil be more easily absorbed when you breath. You actually get more health benefits this way. They work well and need to be cleansed occasionally. Instructions come with the diffusers on how to clean them. I have one kind that can be put into the dishwasher. Too bad I don't have a dishwasher. I let mine run out of oil completely before I shut it off. This prevents the oil from sitting in the oil holding area and becoming thick. You can run this kind around the clock if you want. I have and had no problems with them. They can be plugged into a automatic timer. I have one in my bedroom that I put for 15 minutes every hour. You can set the timers however suits your needs best, or don't use a timer at all. I really like this kind of diffuser. I think it's my favorite. I already have two and am seriously thinking of picking up another one. The disadvantage of this kind is you can't put thick essential oils in it.
Since glass diffusers break the oil small enough that it will actually stay suspended in the air for several hours. If you are using a essential oil like lavender that has anti-fungal, anti-bacterial, and anti-viral properties it will actually kill some of the germs floating in your air. It's been said it will even reduce the amount of airborne chemicals in the air.
I have tried to cover some of the methods of using essential oils that I know of and /or have tried. There are probably many more out there. I hope this helps you some.