Place the sugar into a 1/2 gallon ball jar and add in 3 cups of boiling water and stir to ensure all the sugar is dissolved. Add your tea bags and let your tea steep till it is room temperature (I let mine steep overnight).
Remove and discard the tea bags.
Add in the SCOBY (your tea must be below 100F) and add 1 cup of kombucha from the last batch as a starter.
Top off your jar till the water line is about 6 or 6 1/2 cups total.
Cover your jar with a non-bleached coffee filter, paper towel or folded cheese cloth, securing it with a rubber band or your ball jar ring (not the metal top). This will prevent fruit flies from getting to your tea.
Let this mixture ferment for 10-16 days depending on your taste preferences. I do not ferment in direct light, but in a room that has ambient natural light. The longer the fermentation, the less sugar will be left. A three week fermentation is pretty vinegary for my taste. I ferment for 2 weeks as my preferred taste and this allows me to turn over my batches every other weekend with ease.
After your 10-16 day fermentation, remove the new "baby" SCOBY that forms (typically on the top) and 1 cup from this batch of kombucha to start another round.
Drink the remaining fermented tea or proceed to a secondary fermentation to create a fizzier drink. You can discard the "mother" SCOBY, put it in your compost, or use it again to double your batch. Kombucha should be kept in the fridge till consumed.