1st step    :  count the no. of valence electrons[ V ]
2nd step   :   now divide V by 8 ,if V >8
                    or
                    divide V by 2 ,if  V <=8                                   -[1]
                    if the remainder is still  not zero then
                   again divide it by 2,                                         - [2]
                   therefore the final value = quotient in 1+ quotient in 2
                  as    shown in the example
3rd step    :  compare the above obtained value with the table given below :-
                   sp          -   2
                   sp2        -   3
                   sp3        -   4
                   sp3d      -   5
                   sp3d2    -   6
                   sp3d3    -   7
ex:- for  c2h6
step  1   -   2[4 ] + 6[1] = 4+6=10
step  2    -   as 14>8 
                   14/8, quotient=1  as remainder  = 6 which is not equal to zero
                    therefore 6 / 2   quotient=3
                  therefore final value=1+3=4
                   comparing with the table given above
                   the hybridisation is sp3.
note -  this is not applicable  to all compounds