I would say avoid this option unless by some quirk of fate you’ve studied the poem before or you’re of Poet Laureate capability. Poems by their nature are esoteric and the chance of making head nor tail of it under exam stress is not good. There are tips if you google but I’m not convinced.
I think you just need to analyze everything by picking out techniques that are used in the poem and relate it to the theme in question and mention how each technique can be used to explain or portray that certain theme (or whatever is mentioned in the question). Do this for language and structure (assuming you know the components of each). If you are unsure still, look online or read examiner commentary of what students tend to do wrong when answering questions on unseen poetry and work on those areas.