Boil a liter of black tea and add the mint, ginger and possibly other herbs in a tea filter. Also add some agave syrup or. The amount can be varied according to taste.
Let the tea with the other ingredients steep for about 5 - 10 minutes, depending on how strong it should be and then cool well for a few hours. When the tea has cooled down, add the juice of a lemon and it is best to put the tea in the refrigerator again for some time or add lots of ice cubes so that it really becomes iced tea.