To brew Kombucha you will need; 
A Kombucha Culture (scoby) , a glass container/jar of some description. We use jars that hold approx 2 L and all the information below is geared towards brewing in a 2 L container. Do not keep your scoby in the fridge!

Tea bags – we use organic clipper green tea, and it is imperative that all brewing is done using a base of ‘real’ tea, be it green, black, white etc. Sugar – granulated (we use organic cane sugar but cane will be great as well or simply white sugar). A tight weaved cotton or muslin cloth and elastic band to cover your jar. Kombucha brews best at a room temperature also air circulation is important to avoid mold.
Okay, boil a kettle full of water. Put 8 tea bags into your glass container (4 bags per L), than add between 160 and 200 grams of sugar to the container (2L brew). With tea bags and sugar in your container, when your kettle boils, pour the boiling water into the container in which you have placed your tea bags and sugar (but NOT your Kombucha!! You will add this later). Stir your boiling hot container full of tea and sugar, then wait half an hour before removing your tea bags, and then leave to cool.

Wait until the container’s liquid is cool to touch. With the tea bags removed place your Kombucha in your container. Please note that your scoby will stay at the bottom of the container or will float – new scoby will grow at the surface within aprox 2 weeks.
With your Kombucha floating in the tea, put a piece of cotton or muslin over the container top, like you do with homemade jam. Then find a spot for your container, this should be somewhere out of direct sunlight and in room temperature.  

Now, judging the readiness of your Kombucha drink is not a scientific process. You will come to ‘know’ when it is brewed, but don’t worry, before you have gained this knowledge for yourself, we offer this advice. Your Kombucha will take between 10 to 14 days to brew. Take a look at the darkness of the tea when you first put your Kombucha into it, then note how the liquid changes color over the passing days. The color will change, to a degree, and the liquid will become slightly cloudier.

Our recommendation is that, after few days you pour a very small amount into a glass and have a sip. If the brew tastes fruity and not tea like, it’s ready, if not, leave it another couple of days and try again. As you get more experienced you will come to learn the brew duration that best suits your taste buds and palette. When you feel your brew is ready, pour your brew into the container you plan to keep your ready made drink in, but remember to leave the scoby sitting in a small amount of the brew in its brewing jar. You can leave new scoby too. Put your ready made drink into the fridge, leave it for a few hours and then drink! The longer you leave it in the fridge, the fizzier it will get, and it can be left without going off so drink at whatever pace suits.
While your Kombucha sits in its jar in the small amount of its own juice, either boil the kettle to brew another batch (that way more should be ready by the time you have drunk your first lot), or if you are not ready to brew some more, cover the top of the jar and leave your scoby sitting in its juice.