How to study literature?

So, I study linguistics and literature at college in Brazil. The thing is since the beggining I was amazed by linguistics and not so much by literature.

However, this semester on my literature class Im really linking and invested in study Machado de Assis (a brazillian author), but I still don't understand the concept of what we are doing. It seems sometimes like it has no metodology because my mind is much more on a greimas semiotic mindset when reading it.

So, what to look for when studying literature, knowing what is pertinent and what is not?

(I intend to have this conversation with my professor aswell, but thinking on how to ask because sometimes professors are dicks)