For Novels/Play's
What I suggest is looking up the main themes in each of those texts, looking up why they are structured like they are, what language they use and why, what are the functions of the characters and what message are the texts trying to achieve.
Especially look for the importance of setting, language and actions/emotions in a play.
Once you know what the authors are trying to do you need to know how they do it and thats where information on structure, setting, character functions and language come in. You need to know how these are used to convey their main message.
You also need to know the importance of any epigraphs/prefaces and the context from which the novel was written. (Important historical factors for example)
You also need to know quotes for any books you are doing and they need to be relevant to the point you are making.
For Poems.
You need to know what the main point of the poem is and have some good points about the characters and the wording in the poem. You need to know about it's structure, rhyme, rhythm and setting as well as the main theme(s) of it.
You do not need to know about the poets for most boards.
Helpful Tip
Use P.E.E.L
Point, Evidence, Explanation , Link
Basically Make a point, back it up with a quote (if relevant -most of the time a quote should be used), explain how the quote supports the point and link the point back to the question.