Question

how is lewis structure made?

Answer 1

1.decide the central atom of the compound
2.first attaching the most electronegative elements of the compound with the central atom
3.now placing other elements of the compound with regard to the octet rule .

please note that the central atom has exactly 8 number of electrons with proper bonding

thanks cheers

Answer 2

you have to use no. of valence electrons in an element..
eg is in the pic above..