This is a follow-up question for this one:
All people in this world are born with some degree of magical power, which increases through training and age. There are different schools of magic, one of them being ritual. This form of magic is formed in groups of nine, called covens. To be able to join a coven a witch must undergo a ritual promise that they will be loyal to the coven. Otherwise the witch is not welcome into the coven. The terms of the contract state that the witch must always help the other members to the best of their abilities, and cannot hurt other members directly. This pact is reinforced by magic, and cannot be broken.
There are those who wish to take a shortcut to power, or to achieve it more quickly than others for their own ends. These people often have a disregard for life and are ruthless enough to do anything it takes to get power. The people often join covens of like minded individuals. Covens dubbed "evil" by the establishment often meet to perform this ritual of stealing the life force of others to make themselves stronger. Ultimately, their purpose is to transcend their physical form to a higher state of being through apotheosis. These godlike beings are a reflection of their inner self and have unique forms. After this state is reached, they ascend to another plane of existence, as gods cannot remain on the mortal plane. The problem is that since one of their members as ascended, the coven is short a sister. Ritualized magic requires a group of nine individuals, otherwise this spell and other types of its kind will not work.
These renegade covens must operate in secret to avoid being discovered and wiped out by society. "Good" covens, the ones considered legitimate, are on constant lookout for their fallen sisters to prevent their goals. This makes finding new members difficult and time consuming. How can these individuals organize their covens in a way that allows them to recruit new members after one has achieved godhood, and at the same time operate under the radar?