The first step in writing your stanza using Poe's meter and rhyme scheme is to identify the metrical pattern of the poem. "The Raven" consists of six-line stanzas. The first fives lines of each stanza are written in a fairly unusual meter of trochaic octameter, mean eight feet in which each foot consists of a stressed syllable followed by an unstressed one. The sixth line is shorter, and is written in catalectic trochaic tetrameter, meaning that it consists of four trochees, but with the final weak syllable of the last trochee missing, i.e.:
/ _ / _ / _ / (with / representing a stressed and _ an unstressed syllable)
The final line of each stanza should end with the word "nevermore." The rhyme scheme of the stanzas is ababba, with the third line occasionally rhyming irregularly.
In terms of tone, the stanza should be melancholic, saying something about "lost Lenore" and in the fifth line ask a question that the bird can answer with the word "nevermore."