Poetry format?

[collielover42]

I have a class assignment to write this minimum 16 line peom. I was wondering when do you put the commas at the end and when you just continue on with no punctuation.

Here is one place I need help

People called him ugly,
People called him wicked.
They said his heart was shriveled
Or that he didn’t have one to start.
But it was there deep down,
Beating just as strong as ours.

are the commas in the right place?
Do I need more?
Where?
Help!!