Mostly I just talk like anyone else, though sometimes my Gran and me talk Patois which is, like, Caribbean slang, well not slang really, but the local way people talk on St Vincent, where she comes from. She knows I don't speak it at school or anything, but it's like a family thing that we do at home when we're messing around.
Patois is like English but it sounds different and not all the words are the same. Some Rastas use a kind of Patois when they're together, so if I wanted to invite you to my house I would say something like 'yu wan cum fi check mi yard?'
People that are seriously into Rastafarianism try to learn some Amharic, which is the national language of Ethiopia where my religion's from.