This is the first book I've ever read on the topic of nail decoration, so I'm not as well qualified to assess the techniques and designs as a professional manicurist. Nevertheless, it struck me as a fun book. It showcased a variety of techniques and the photos and instructions looked easy to follow.
The photos are on the sloppy side, though, with lots of issues like nail polish either not fully covering the model's nails or flowing over onto the model's skin. To be fair, the nails are depicted at several times life size, so any mistakes are going to be easier to see.
The nice thing about the photos in this book is that if you're an amateur, you can look at them and feel reasonably comfortable that your work is going to look at least that good. You can go forth, have fun, and not obsess over perfection.
If professional nail artists or manicurists have a better book to suggest, it would be nice to hear what it is.