As far as the promised health benefits are concerned I have noticed a marked improvement in my afternoon energy levels and I am convinced my immunity has been kicked up a notch as I can't recall having so much as a cold since we started drinking kombucha daily in October. That's a pretty good track record.
I've seen all different sorts of set up, but the following is the one that works for us
Brew strong black tea and sweeten with sugar, cool to room temp and add scoby and 1/2 cup to 1 cup of fermented starter (this comes with the scoby for the first brew, but afterward you'll need to set aside some of the first fermentation liquid each batch to start the next batch). Cover with a paper towel and wrap with seedling heat tape. Try to keep brew between 75-80 degrees (optimally). Let stand 4-21 days depending on amount and desired fermentation. After about 5 days I start smelling and tasting the brew every other day until it reaches the level of acidity we like.
Remove scoby and add the desired flavorings, cover, and let stand another 2 days.
Strain and bottle. Add a pinch of sugar to each bottle. Secure the caps, shake the bottles to distribute the sugar, and set aside for 2 more days. Refrigerate and enjoy. With this method you may find a tiny baby scoby in each bottle. Many kombucha enthusiasts ingest the baby scoby. We don't because it has the consistency of snot (blech!). We strain the kombucha into a glass and discard the baby scoby.