SIGNAL is built to be opened, not read straight through. Each of the 120 entries is self-contained: a behaviour, what it tends to mean, the context that produces it, and what it is most often confused with.
Browse by number when you want the full sequence. Browse by meaning when you have a hunch and want to test it. Use ⌘K to search by name, body part, or association.
Read the entry, then read what it should not be confused with. Most misreads happen there.
Save what you want to return to. The book remembers nothing about you, but it will remember which entries you marked.