There was one summer, when my children were being tutored in Berkeley, that I worked on a lot of jigsaw puzzles in the waiting room. The challenge was entirely visual. After a while I figured out a system of approach, and the pieces fell into place quite easily.
Consider the invention of writing was initially regarded as secret codes possessed by the privileged few, poetry is like a puzzle too. Metaphors, puns, visual clues, stresses and form are some of the tools to create multiple imageries and meanings. It is theater. It is a secret letter. It is an open invitation to play.
To find the key: observe.