Well, I have nothing but praise for the Oxford "Very Short Introductions" series, and two of the books on the list are part of that series.

Nevertheless, one may know all there is to know about sleep and still have terrible sleep hygiene (often caused in part from other bad habits).

Call it "grandmotherly wisdom" or anecdata, but the following have never failed to deliver great sleep for me (and vice versa):

- minimize caffeine and sugar intake, and stop consuming them by early afternoon

- eliminate alcohol intake

- 1–3h of exercise per day, 4–6 times per week

- try to get up at the same time every morning

- no late-night TV / device use

- no drugs

FWIW.