Put the lemon balm and mint with the stems in a jug. You can also cut them into small pieces about finger-length with kitchen scissors. Do not chop or the essential oils will evaporate. Add sugar (you can leave it out) and pour the hot (maximum boiling, not boiling!) Water. Then let it draw covered. After about 20 minutes a very refreshing lemony-minty taste has developed, the longer the brew is left, the more intense the taste.
You don`t have to take the herbs out, but I usually pour through a sieve into bottles and keep the tea cold. It`s great after exercise! If you want, you can just take lemon balm or change the quantities. My mother always did it that way.