1) Write down the number of the month you were born 2) Multiply it by 4 3) Add 13 4) Multiply the result by 25 5) Subtract 200 6) Add the day of the month on which you were born 7) Multiply by 2 8) Subtract 40 9) Multiply the result by 50 10) Add the last two digits of the year of your birth 11) Finally, subtract 10,500