Caim's entry contains an odd procedural detail: he answers in burning ashes, or out of coals of fire. It is one of a handful of places where the catalogue describes not what a spirit gives but how it communicates.
Read historically, this is pyromancy, divination by fire, and specifically by reading the behaviour of flame, embers and ash. The practice is ancient and widely attested in Greek and Roman sources, sits alongside the better known divinatory disciplines, and survived into medieval and early modern Europe in domestic forms. The Goetia touches it, names no method, and moves on.
That reticence is characteristic. The catalogue is not, in itself, a set of instructions. It says what each spirit looks like, what it commands, what it can do, and what its seal is. The operative apparatus is in the front matter of Book One and is not tied to individual entries. A reader looking for a procedure will not find one in the seventy-two, and the seventy-two are the part of the Lemegeton that has been reproduced most widely, usually stripped of everything around them.
Which produces the situation the corpus is in today. The catalogue circulates as a bestiary, a reference list, a source of names, and increasingly as source material for fiction, games and music, where it functions purely as a stock of evocative attributes. Those uses are not misreadings of a working manual. They are reasonably faithful to what the catalogue actually is: a descriptive list, in a book whose operative sections are elsewhere and are rarely reprinted alongside it.