This may seem like an odd question but I believe there absolutely should be a standard or most common way to use LaTeX on emacs, and that this community would benefit from owning a complete answer to this question, so here goes.
This is my first Google hit for "emacs latex mac", which seems to imply AucTeX is the way to go.
I'm trying installing it now but I'm not sure how out-of-the-box it is. The wiki says:
C-c C-c to run LaTeX over your document, then, once it has compiled correctly, C-c C-c again to view it, or if it failed to compile correctly, C-c ` to see the errors.
C-c C-c doesn't do this (it brings up a prompt).