The oxidation levels typically range anywhere from 5% to 80%, meaning that the process can change drastically from farmer to farmer. Because it has the widest range of oxidation states, there is a large variety of flavors that are constantly being refined by farmers. This results in some of the most unique flavors that can be found in tea, ranging from silky smooth and milky, to fruity, to dark and rich.

On top of the large range of oxidation and also partially as a result, oolong also uses the widest range of techniques for preparing. Although there are core steps that remain the same no matter which tea you look at, the specifics can vary quite drastically. After picking the leaves are left to wither usually in the sun, or in an indoor environment although this is not as common. This starts to dry out some of the moisture content and adds stress to the leaves which make it release the hormones that we relate to flavors, and also helps in decreasing bitterness. Next comes a process called brushing, where they toss the leaves around several times in order to gently bruise the leaves, starting their oxidation process. The more they bruise the leaves, the faster and therefore more the oxidation occurs. A lot of key variations occur in this step according to what the farmer is trying to achieve with their oolong, although typically the amount of oxidation is similar to others in the region. The next step is called "kill green," which is essentially a cooking process which results in stopping the oxidation, as well as giving a chance to change the flavor profile through different cooking methods. All the different cooking techniques use very high temperatures for a short time, around 500°F for a few minutes, to stop the oxidation process as quickly as possible to set the flavors. After the kill green process the leaves are rolled to varying extents, with some being rolled into tight curls and some being left as mostly long leaves. This helps push the flavors onto the surface of the leaves as well as giving it a unique presentation. Finally they go through a more gentle drying process to bring the water content of the leaves below 5%, this helps bring out a lot of the aroma of the tea as well as prepares it for storage.