Enter your own words or phrases one by one. After each word or phrase click "use this" to add it to the list. When you're ready, click "Re-make the poem". You can come back and add more words in each box (and click "Re-make the poem" again). To clear your word lists, click the "Use my own word list" button again.
Note: the system is fairly flexible. The words don't actually have to be nouns, verbs, etc. They can be any syntax elements, which will be put together in order, chosen randomly from each list.