Get very familiar with the table of contents first. Then note and filter out the sections you are less interested in or don’t appear to provide the biggest bang for your buck.
Annotate, annotate, annotate. Active reading is better than passive reading. I use a 2-in-1 chromebook and a passive pen to highlight in the adobe pdf reader.
Write detailed notes in addition to annotating (i.e. in a separate notebook or markdown file). Cull/convert your notes into Anki/Memrise digital flashcards. Drill on your phone when you are lying in bed.