It's simple. You post 16 bars - no more, no less. The person below you posts hit it or quit it. You judge the person who posted above you.

Sittin in this room like a prison
Tied to my commitments
Wonderin if I will ever finish
What good is all the glory when your whole's story's boring
Sittin in a cave workin like a slave who's sorry
I just wanna live my life but
I just gotta do **** right yup
Got one damn chance
So sick of romance
Done a lotta **** but I had to advance
Focus on me but it got me feelin lonely
All my prized possessions nothin a blessin but
What is the purpose with no crew
Ambivalent homie prolly just like you
So put it in some doja lemme light it for ya
Tonight I'm gettin lifted but this one's for you yeah