This is an assignment you perform in front of other students. You essentially need to make a silent conversation between yourself and the "aliens" to try to figure out what you are saying to each other. That is as much as I can help you with, as I have no way of demonstrating it for you :)
Onomatopoeia.
Imagery is incorrect as poets use that in order to help a reader visualize the scene or actions within the poem.
Simile is incorrect as similes are used to make analogies or comparisons between two objects or things.
Personification is incorrect as it is used to give a non-human being humanistic traits, for example, "The wind sang throughout the cold winter night."
Onomatopoeia, however, is correct as this is used to term sounds within a poem such as Wham! Bam! etc.
Hope this helps!
They managed it despite the fact that i wasn’t there.