I'm somewhat of a paper engineer myself so it didn't bother me that there were no instructions. It's easy enough to figure out by the actual pop ups and the geometric ratios provided. There were some elements I have never seen before and a lot that I had seen before. It was nice that there is a lift up flap in the back where you can observe the inner workings and easily take it apart if needed.
It's a nice reference book for all kinds of folds and pop ups plus some fun motion type cards that don't actually pop up but move. If you are already comfortable with making action cards or pop ups, you will enjoy this book. If you are a newbie to this kind of card, you may be frustrated by the lack of measurements and instructions to make each element. Don't buy the book if you need someone to dictate exactly how to make the element.