essentiel oil mixture at backing soda rinse

Hey good chritsmast evryone

For christmast my mother bought me three kind of essentiel oil. I have watermelon, mandarin orange and Lavender rose. Do someone know who I can use them in backing soda rinse and how many drop I need for each? Can I do some mix with them?

Thanks a lot for your help.

updated by @gabriel-beauchemin: 01/13/15 09:16:05PM

I would't do more than 5-7 drops per liter, cause essential oils have a real strong smell. But i'm

not sure of watermelon harmonies with mandarine. Try it out.

Merry XMAS!