Find your birth year
Add the digits of your birth year together until you get a single digit
For birth years before 2000, use the last two digits of the year if needed
For birth years from 2000 onward, add all four digits until reduced to a single digit
If you are male, subtract the single digit from 10
If you are female, add 5 to the single digit
If the result is a two-digit number, reduce it to a single digit
If the result is 5, use 2 for males and 8 for females
The final single digit is your Kua number