Good morning Isabelle,
Thanks for asking, and fair warning , this will be a bit long. First off, a few words on ginseng. Roots are a bit pricey, capsules not so much. If you use the capsules, peruse the labels carefully, as many will have little ginseng. Ginseng has many "benefits", as you may search and discover, one of which being its' ability to be used as a testo booster. A simple adjustment of whatever anti-andro you use should cover this. Honestly, I've been using 5 mg Premarin and 50 mg Cyproterone daily for a year, and the ginseng has been of no revelence as far as NBE. I'm at a full 38B, and the little "fella" is extremely hard to arouse ( no pun intended), and at full stream manages maybe a dewdrop. I feel that as a tea it is probably of less strength than powder or capsules, especially if one is of the "if 1 is good, more must be great", attitude. Yes, I've been a member of that club, too. In short, check out the ginseng info before you decide. Lastly, there are different types of ginseng. We use Korean red ginseng, grown 10 years, then the soil is rested 10 more years before planting. Surely has something to do with the price.
Now, to really get to your question. Her slow cooker holds approximately 2 quarts/litres. In this, she places 3 roots, about 3/4-1 inch diameter, and 4-5 inches long. Water is added to within about 1 inch of the top, and the cover is put on. Cover is not a sealed type, so water can boil off slowly. She sets it on high, which on a slow cooker is not extremely hot, but does BOIL the water, as evidenced by some steam and bubbles escaping the rim of the cover. (A caution, if you leave it on overnight, set it to low, to continue the process, but lessen the chance of possibly drying it out). The brewing should continue untill such time as the water level is about 1/2 of what you started at . Pour into a container, cap it, and start anew. Yes, those pricey roots will yield a total of at least 4 batches, maybe more if you don't mind weaker tea. We hold at 4, and it maintains consistency very well. If you go for more, then I would consider using another for the finished tea. We put all 4 in one container. She uses it atraight, but I have to have mine with honey. Tea to me is like whiskey without the sour. Depending on the size of your root

, you can always adjust the amount of water, I imagine. The process should be nearly identical.
As a side note, I have changed my regimen since I received my PM. I now take only 2.5 mg of Premarin, same 50 mg of Cypro, 3000 of PM, and 900 mg of SP, all /day, and split up in 2 dosings, maybe a bit excessive, but absolutely no ill efects. Still taut, and still mucho tenderness around the nips, which I take to mean there is still growing going on. Mom and sis were easy DDs. Yes, they do show, and no, I really don't give a rat's a-- . (Like I said, I've played with the "more is better" crowd a time or two)!! Went to the doc today for a rash, and got a steroid shot for the itching, and pills for..Yeast Infection!!! Am I arriving?? Interestingly enough, she said nothing when I raised my sweater and she saw the "Girls", with no hair in sight.
I know, long-winded, but I hope I've answered your questions.
We're all riding a "horse of adventure" here, and what a journey it has been so far!! Take care, Patti