I make an infusion (steep over night) with 3 (heaping) tbsp of the loose leaves to 3 cups water and drink that throughout the day.
My infusion also has alfalfa (1 tbsp), nettle (2 tbsp), and burdock root (1 tsp). My MW said 1-3 tbsp of each but I have adjusted it to my taste (burdock tastes really bad, btw).
I don't think RRLT will reduce your milk supply. I drink this stuff every day and I hand express about a tablespoon's worth of colostrum from each breast on a daily basis... and I don't even have the baby yet!

(maybe it's the alfalfa?)