Puerto Rico customs

Question

I am going on a mission trip to Caguas, Puerto Rico, as a 'training trip' before I go to a non-english speaking country. I know that many people in Puerto Rico speak Spanish, so I was wondering if ya'll would be willing to share some info on Puerto Rico, such as popular phrases, slang, customs, etc. Anything you would be willing to share would be helpful. Gracias, amigos!