Identify the central atom or ion
Count the number of atoms, ions, or ligands directly bonded to the central atom or ion
Include only nearest neighbors in the first coordination sphere
Do not count atoms that are farther away or only indirectly connected
For complex ions, count each ligand as one coordination unit unless it binds through multiple donor atoms
For polydentate ligands, count the number of donor atoms attached to the central atom
For crystal structures, count the number of nearest neighboring atoms surrounding one atom
Use the molecular or crystal structure to verify the total number of direct bonds around the center
The final count is the coordination number