I have purchased quite a few of Sherry Nelson's other books and found them excellent. This book I found disappointing. The diagrams of the intricate parts of the butterfly body and wing might have been fine for a butterfly anatomy class - but not an art painting book. But I could have ignored that if, on each instruction page, they had put a straight line from the part of the butterfly wing or butterfly body the author was referring to and the text describing how to paint that area.
Unfortunately, they did not do that! Instead, the reader was expected to thumb back to the labeled butterfly diagram in the front of the book, just so you could understand each painting instruction. That was a total turn off for me. I was also disappointed on the size of the butterfly images inside the book. Had they been larger it would have been a lot easier to follow the instructions on how to paint that area. I have enormous respect for Sherry Nelson as an artist and a teacher. I think it is a shame the book was laid out in a way that was not what I would call 'user-friendly'