State the points required for Lewis dot representation.

(N/A) $1$. Total number of electrons in a neutral molecule: The total number of electrons required for writing the structures is obtained by adding the valence electrons of the combining atoms. For example,in the $CH_{4}$ molecule,there are eight valence electrons available for bonding ($4$ from carbon and $4$ from the four hydrogen atoms).
$2$. Number of electrons in a negative ion: Each negative charge means the addition of one electron to the total number of valence electrons. For example,for the $CO_{3}^{2-}$ ion,in the Lewis representation,there are a total of $24$ electrons: $4 \ e^{-}$ from one carbon,$18 \ e^{-}$ from three oxygen atoms,and $2$ additional $e^{-}$ due to the two negative charges.
$\left(\begin{array}{c} \text{Number of} \\ \text{electrons in} \\ \text{negative ion} \end{array}\right) = \left(\begin{array}{c} \text{Total valence} \\ \text{electrons} \\ \text{of all atoms} \end{array}\right) + \left(\begin{array}{c} \text{Number of} \\ \text{negative} \\ \text{charges} \end{array}\right)$
$3$. Number of electrons in a positive ion: Each positive charge means the subtraction of one electron from the total number of valence electrons.
$\left(\begin{array}{c} \text{Number of} \\ \text{electrons in} \\ \text{positive ion} \end{array}\right) = \left(\begin{array}{c} \text{Total valence} \\ \text{electrons} \\ \text{of all atoms} \end{array}\right) - \left(\begin{array}{c} \text{Number of} \\ \text{positive} \\ \text{charges} \end{array}\right)$
For example,$\left(\begin{array}{c} \text{Total} \\ \text{electrons} \\ \text{in} \ NH_{4}^{+} \end{array}\right) = \left(\begin{array}{c} \text{Valence} \\ \text{electrons of} \\ N \ \text{and} \ 4 \ H \end{array}\right) - 1 = (5+4)-1 = 8$.
$4$. Distribution of electrons: Knowing the chemical symbols of the combining atoms and the skeletal structure of the compound,it is easy to distribute the total number of electrons as bonding shared pairs between the atoms.
$5$. Position of electrons: After accounting for the shared pairs of electrons for single bonds,the remaining electron pairs are either utilized for multiple bonding or remain as lone pairs. The basic requirement is that each bonded atom attains an octet of electrons.