Zi, Wu, Mao and You are a fixed group of earthly-branch positions. The “three directions and four positions” reading network is different: it depends on the palace chosen as the reference.
Try a reference at Chen
Chen connects by the triangular relationship to Shen and Zi, and faces Xu. Including Chen itself gives Chen, Shen, Zi and Xu.
Move the reference to Si and the network becomes Si, You, Chou and Hai. Neither example describes the fixed Zi-Wu-Mao-You group.
Add palace names after locating the cells
For the natal Life Palace, the network corresponds to Life, Wealth, Career and Travel. A different reference palace requires different palace names. Decade and annual readings must also specify their timing layer.
Do not substitute the top, bottom, left and right edges of a square screen for these relationships. Display orientation can change while the branch relationships remain the same. Locate the four cells first, then interpret their stars.