I use oils often. I put some in the air using the difusser then one him after bath time. I might use them maybe 3x a day. I do not think there is a limit of how you can use them but if you feel too overwhelmed by the smells then air out. I do give a day of break from me though.

I'm professionally trained and so have a professional outlook on this question. It depends on the type of oil in a BIG way. There are many ways to use essential oils from diffusing in the air with a diffuser, making a spray by adding proper dilution to water in a glass spray bottle, adding to a carrier of some kind like an oil or lotion, or simply sniffing "neat".

Can you say more? What is your intention specifically with essential oils? What are you wanting to effect specifically? Ie, calming, focus, health, etc. Describe what you hope to "treat" with essential oils and in what setting/ time of day, whatever you can share that is pertinent.

What are you currently using and how? I've had my own essential oils company in the past where I sourced all of hundreds of oils directly from distillers all over the world, am very familiar with companies and oils, quality etc. and have consulted with companies and individuals on safe and effective use, blends, etc. for decades.

Essential oils are all very different depending on the specific type of plant. Some are much more gentle than others. That does not mean not to use others necessarily, but to be informed about safe and good practices.

Given the fact that many people learn about eos from MLMs and people selling oils, as well as massive misinformation on the internet it's easy to be confused about what is true or not.

It is not what I am currently doing (for past 8 or 9 years) professionally, but I am happy to offer any feedback I can.