For instance lavender is good for stress. A mixture of clary sage and ylang will help depression. A good wake up formula might be geranium, rosemary, and peppermint. About ten drops of concentrated oil added just before bathing is average. It takes twenty minutes for the oils to enter your bloodstream with inhalation or skin contact.
Essential oils are powerful.
In most cases essential oils should be used diluted. If you are going to use them full strength check a small area for skin irritation first before using. Never go into sunlight after an application of bergamot, verbena or citrus oils. Basil, clary sage, hyssop, juniper, marjoram, myrrh, pennyroyal and large amounts of peppermint. Avoid all toxic and semi-toxic oils.