Chinese Astrology - diagram from Konni's Blog - chinese astrology 2010
(Note: I like the graphic, but can't say much about the site. Offers a chinese astrology 2010 download, but when I clicked on it an alarming pop-up came up rsayiong my computer contains numerous viruses and malware, and requesting a virus check. This put me off downloading, as my anti-virus software is upto date)
Because I'm lazy, and more importantly because I have so much to do and because this subject is well-known, I'm quoting here from the Wikipedia page "Astrology" and Chinese astrology
"Chinese astrology is based on the traditional astronomy and calendars. Chinese astrology does not calculate the positions of the sun, moon and planets at the time of birth.
The development of Chinese astrology is tied to that of astronomy, which came to flourish during the Han Dynasty (2nd century b.c.e. to 2nd century c.e.).
Chinese astrology has a close relation with Chinese philosophy (theory of the harmony of sky, humans and earth) and different "principles" to Western: the wu xing teachings, yin and yang, astronomy: five planet, the 10 Celestial stems, the 12 Earthly Branches, the lunisolare calendar (moon calendar and sun calendar), the time calculation after year, month, day and shichen.
In contrast to Western and Indian astrology, the twelve signs of the zodiac do not divide the sky, but rather the celestial equator. The Chinese evolved a system where each sign corresponds to one of twelve 'double-hours' that govern the day, and to one of the twelve months. Each sign of the zodiac governs a different year, and combines with a system based on the five elements of Chinese cosmology to give a 60 (12 x 5) year cycle. The term Chinese astrology is used here for convenience, but it must be recognised that versions of the same tradition exist in Korea, Japan, Vietnam, Thailand and other Asian countries."
I do not think Chinese astrology is hard to follow, especially if you are familar with Chinese Medicine, Feng Shui, or Taoism. However it does have a lot of basic details, like all such esoteric and holistic systems of knowledge. The Wikipedia page on Chinese astrology has more information on all this, so pending upgrading pof the page and additional material and links, I'll leave it at that for now.