As UnluckyRaven put it in another post, it is ''pure eclectia''. Essentially, the Chaote tries many things, many beliefs and practices, to find out what works best for them in a given situation. And when it no longer works, or you find something better, you drop your old paradigm and shift to a new one. It focuses primarily on the power of belief; you shift beliefs so that what you want is possible. For example: currently you are of X religion (or mind set), and this system of belief does not allow for say, astral travel. You research the subject a bit and move to Y belief, which encourages the reality of astral travel so that you may more easily accomplish it.
The ''law of Chaoism'' is ''Nothing is true, everything is permitted.'' I have seen this described by a mental diagram of imagining a bag. Inside this bag is everything in the Universe (including the bag itself), and for it to have absolutely everything inside it, it also has nothing inside it. Chaos magick philosophy gets very trippy.
I recommend reading through http://www.chaosmatrix.org/
It isn't really active anymore, but the archives are full of very useful practices/techniques and essays on the subject.
Also, next time, please use the search function here on the site to bring up old topics where stuff has already been discussed; feel free to revive them.