As someone who finds himself practicing without the benefit of a teacher or master, I found this overview of Dzogchen to be helpful in clarifying what it is I am trying to do, and why. It is experience-based, concise and inviting. The first part lays the groundwork for understanding what Dzogchen is and is not. The second part is a brief guide to its practice.
This book is excellent. It may be required some knowledge of the topics to better understand it, although this is not a demand. It is written in a very easy language easy to understand even for people that don't speak english as a mother language. It contains a helpful advice on how to confront daily live in a better way, although it comes from very ancient fonts of knowledge. The contents are still actualized, maybe because the basic problems of humanity are still the same (since the beginning).