How/When to best use a Study Guide

We received our copy of the new Princeton 2020 APWH guide yesterday. The “how to use” section advises to start by taking the first practice test. Given that my D is only about 1/3 of the way through the course content, this seems like a waste of time.

Anyone have experience-based advice on when and how to best use the 5 sample tests and review material, in the context of a class starting in late August and going through the early May test date? All of the material won’t be covered until shortly before the test date, but waiting until then doesn’t seem to make sense either.