System Overview

In a nutshell, this is a theurgic system that aims to unite the postulant with the Dragon.

It does this through a series of rites over two years.

Chumbley helpfully summarises the basic practices on pp61: In addition, there are seven major rites throughout the year: the rites of Hu, Su, Ba, Ku, La, Tan, and Hua. Chumbley recommends that any aspirant should go through the full forms of the rites at least once before messing with their structure, which seems sensible.
 * The Marriage Rite
 * The Midwinter Rite
 * The Stellar Transvocation
 * Oracle Rite at each Dark Moon
 * Yearly convocation of Thu'ban

He is keen to stress throughout the book, however, that despite this, the path is fundamentally one of sudden illumination, and ultimately there is no specific combination of words that can cause that to occur- what's presented in the book is just one representation of the path, it's up to the postulant to actually tread it.

This interview with Peter Hamilton-Giles (a Cultus member [possibly former?], and one of the founders of the Column of the Crooked Path, which created the Dragon Book material) is well worth reading- he discusses the influence of Haitian Vodou on the creation of the system. One interesting point raised in it is that the rites a a combination of a number of different magical currents, especially Stellar Gnosis (Thelema is another example of this), Essex Witchcraft and Haitian Vodou. It's a good example of how currents can enrich each other in combination.