All essential oils need to be diluted in a carrier oil, as they can be too strong or even cause irritations and sensitization if used in pure form. Some essential oils can be edible with proper precautions and dilution. Some like Peppermint, Tea Tree Oil or Lavender can be mixed with toothpaste, or added to water and used as a mouth wash. Peppermint and Lavender can also be added to hot water and consumed as tea. (start with 1 drop for 1 cup water)
Carrier oils are extracted from Sweet Almond, Jojoba, Avocado, Castor, grape seeds etc. in a cold press and processed very little so that they can be used on skin without being sticky while maintaining their nutritional value. You can also use a natural cream, vegetable butter like cocoa, shea nut, etc.
How much Essential to use.
Total number of drops of essential oil for 30 ml (2 tablespoons) carrier oil, cream, or other natural cold pressed lipid is 12 drops. This gives you a 2% solution, which is considered safe for most adults. Cut this in half for children and those with sensitive skin.