NavList:

Igor S, you wrote:
"I was wondering, how the lunar method was taught back then ..."

Back when? Lunars were taught even longer than they were actually used at sea. The period in which you could find textbooks with material on lunars ranges from about 1763 (*) to about 1915. That's a century and a half. There's a vast variety of instruction in a century and a half of history! Are you looking for something distinct from what's found in the navigation manuals? Essentially every navigation manual had at least some instruction on lunars. Most were just dry walk-throughs of the math, but some offered more general advice. Even Lecky, who reminds his late 19th century readers that lunars are "as dead as Julius Caesar" (and he was quite correct in the context he describes), offers rather extensive practical advice. The great majority of the pedagogy of lunars is now entirely lost to us. Lunars were primarily taught by real people in classrooms and aboard ships at sea. Essentially none of that in-person education has survived.

Frank Reed
* From the earliest period I suggest Maskelyne's "British Mariner's Guide". But where is it? Can anyone find a copy online? I have a PDF of this somewhere, and I will make it available if there's no easier solution.