Begin by tracing the drawings and then using the guidelines to harness your own creations. As long as you fill out every page, it doesn't matter if you follow the guidelines exactly. Instead,you will build an understanding of how the human body is constructed and how three dimensional objects can be represented with lines. Try using various methods such as construction, contour drawing or your own technique.
Once you've completed the thousands of drawings, you will have a record of your progress and have a much better understanding of the basics of the human form. This is meant to be a workbook, so go ahead, start drawing!