Numerology is similar in some ways to astrology. It takes different aspects of your life, including your birthday, and tells you about yourself using numbers. There are many ways numerology can be used, but the most commonly known is to use your birthday and name.
The first is fairly simple. You take your birthday and add the numbers together. For instance, if your birthday is April 17, 1976, you would add 0+4+1+7+1+9+7+6 and come out with 35. Then you add both numbers together, so you'd add 3+5 and come out with 8. That is your date of birth number.
Now for your name number, you can do it one of three ways: your whole name, the vowels, and the consenents. Each number reflects differently on you. I'll give you and example, using John Joe as the name.
First you have to figure out which letters equal what numbers. I've provided a table below. The letters go from 1 to 9.
Then you take your name and figure which letters correspond to which numbers and add them up.
Then you simply add the numbers up and reduce the number to a single digit like before. So it would be 1+6+8+5+1+6+5=32. 3+2=5. So that's your whole name number. You would do the same thing for the vowel and consenant numbers, just using one or the other. (For the vowel number, only a, e, i, o, and u are considered vowels.)