Pour the olive oil, lecithin, and alcohol into the bottle. Cover the opening and shake until fully blended; the lecithin helps the oil travel up the reeds.
Add the essential oils, cover, and give it a light shake.
Put on the collar if you are using one, then set the reeds in the bottle.
After 30 minutes, turn the reeds over, and after another 30 minutes, turn them over again.
Put it somewhere it will not get knocked over.
Notes
Flip reeds once a week. Lasts about 1 month per ounce of carrier oil (3 to 4 months for this batch); replace oil and reeds together, reuse the bottle. Safety: keep out of reach of children and pets; a tipped bottle or chewed reeds can poison them. Peppermint, rosemary and citrus oils are toxic to cats and dogs; don't place where pets sleep or can brush against it. Oil stains surfaces: set it on a tray or coaster. Not for eating.