You must write a 2 line rhyme using almost only the same letter at the start of all words (small words like "a" and "the" are allowed) that the previous person leaves for ya. Then you leave a letter for the next guy.
I`ll start with the letter "A".
Activate all aristocrats of alliteration, act to annihilate and alienate airheads,
Amass all arms, aim and assault, advanced adverbs attackin ancient adults
This is a pretty hard cypher, but don't lose faith, or worry about your standard, we'll improve with more practice.