Never Pretend to Be a Unicorn

I found this in my in-box today. Some advice to poets -- but let's just call it some wise words to People in General, with a wink and a sense of humor. Advice to Young Poets

by Martin Espada

Never pretend to be a unicorn by sticking a plunger on your head 

Here's what I think it means. Well, I'm just going to think on it. I don't want to rob you of your meaning! But do share.