Did you post this a few days ago? You havent started yet?
I think I suggested to you the narrative style was centered on the narrator seeing the events and knowing things that the characters did not, and they told a story. In Beowulf, the story was an epic, you dont want to do that I am fairly certain. So just start a story, poem style, that weaves a story as told by and outside observer. I did give you Poe's Raven, which is a simple poem, describing Poes recurrent bouts with recurring alcoholism and depression. I am uncertain what more I can do, I cant write for you.
Put a story or situation you want to tell in your mind, make a short outline. Perhaps something in your life that has stuck as a lesson, or a situation to avoid. Lord, we all have had those. But keep from telling it as you experienced, that is narrative style, yes, but it is first person narrative. You need to write it as an outside observer would see and record it.