Identify the electron configuration of the atom or ion
Locate the specific electron in the configuration
Determine the principal quantum number, n, from the shell number
Determine the azimuthal quantum number, l, from the subshell type
Use s = 0, p = 1, d = 2, f = 3
Determine the magnetic quantum number, m_l, from the orbital orientation
Use values from -l to +l, including 0
Determine the spin quantum number, m_s, as +1/2 or -1/2
Assign +1/2 to the first electron in an orbital
Assign -1/2 to the second electron in the same orbital
Apply Hund’s rule when filling degenerate orbitals
Check the Pauli exclusion principle for valid quantum number combinations
Verify that all four quantum numbers describe the chosen electron correctly