Go stanza by stanza is the only option that makes sense.
To analyze a poem you WANT to read it more than once and pay attention to all the metaphors. Writing your own poem will not help analyze another poem one bit.
The best way to analyze a poem is to go stanza by stanza. This is because a stanza usually has the same purpose as a paragraph in a text: it expresses a single idea. Therefore, looking at a poem in this way will allow you to analyze a full idea without getting lost or confused by looking at too much at the same time.
