I use Thieves every single day, on both me and my daughter. This is a "hot" oil which means it may feel hot to your skin, so you definitely want to dilute this oil by mixing it with a carrier oil such as fractionated coconut oil, sweet almond oil, or grapeseed oil, just to name a few. So far I have only used fractionated coconut oil but I plan on trying another carrier oil when I run out of my current supply of the coconut oil. You can find these oils at health stores or Amazon, which is where I got mine. Thieves is best known for helping to support a healthy immune system so every night before bed, I take my daughter's roller bottle (filled with 2 drops of Thieves and the rest carrier oil) and rub it on her feet. Then in the morning I put it on my feet (although my roller bottle has more drops of Thieves in it) and on my daughter's feet. I put it on more often during the day when needed. The feet is a great place to apply oils topically because they are less sensitive than other areas of the body and the pores on your feet allow the oils to be absorbed more quickly. Another place I like to apply Thieves to on my daughter is her spine. Side note: there is a lot of controversy on the use of oils and kids, use your own judgement when it comes to this. I have read that Thieves is not recommended for use on children under 18 months. But again, it is up to you on whether or not you want to use essential oils on your children. Just make sure you are using a good quality oil such as the oils that Young Living sells.
This is also a great oil to diffuse in a diffuser to support the immune system. Today I had it in my diffuser with some drops of Christmas Spirit and it smelled wonderful! If you want your house to smell like it has been freshly cleaned (but it really hasn't been), then Thieves is the oil to use!!
Young Living also has a line of oils called Vitality. Young Living oils that have this label on it means they are safe for proper internal use. I haven't tried the Thieves Vitality yet, but it is suggested to put a drop of it in your morning juice, tea, or coffee for a flavor boost. You can also add a drop to your oatmeal, granola, or other cereal. Even just adding it to a cup of warm water or milk will help your immune system.
Thieves is definitely an oil I never want to be without, especially during the cold months!