Bear in mind that, although cheap, this is a booklet - it's 18 pages in all, and which makes it very tiny. Although some of the tips are clever and insightful, it's still a high price for the amount of content. Some of the tips are brief summaries of fairly complex techniques, and don't really give you enough to implement them. It appears to mostly be an advert for the authors training - if you know little about this topic already, this book won't help. It is a potentially useful summary of some basic ideas, however.