How do I write an unseen poetry answer?

If you have the option to choose from a selection of poems, choose one that you think you can understand, in a style with which you are familiar.  While reading the poem, highlight as many literary devices as you can.  You should be looking for things like metaphors, similes, alliteration, enjambment, personification, end-stopped lines, etc.  Once you've done this, go through the poem and work out the rhyme scheme, and have a look at the meter, to see if you can work out what its form and genre.  Once you've gathered this information about the poem, read it again and try and decide what it is about and what you think the author is trying to say.  Make sure you identify any tonal shifts in the poem as these will point you toward the narrative voice.

Your introduction and conclusion do not need to be long for this kind of question.  You really just need to explain what you think the poem is about, and what the writer is trying to say with it.  You can then spend the rest of the essay explaining how they do this.  Try to divide your answer into paragraphs, each of which makes a specific thematic point, which you back up with as many examples from the text.