Elder - Anti-Dandruff Hair Rinse

4 handfuls fresh elder flowers, 2 liters water, 2 liters cider vinegar. Boil the elder flowers in the water, cover and simmer for ten minutes. Remove from the heat and infuse for an hour. Strain and add the cider vinegar. Bottle. Leave for 48 hours before use. After washing your hair, add half a liter to the final rinse water.