You seem like a friendly bunch over here so maybe you can give some tips and advice.
I'm especially nervous because it's a phone interview - I can't see the people I'm speaking to!
Most important: what will they be asking? Maybe you can give me some samples.
I wouldn't want to prepare at all, but I know when I get nervous I forget that I can speak english. And I give such dumb replies that I'm embarassed afterwards .
How should I appear, serious or jolly? It's easy to say be yourself, but in such a difficult position it's hard to come across as yourself and not well... just clueless. Do you know anybody from the gift shops? What are they like?
Show me someone who wasn't nervous going to their first interview on a cruise ship, and I'll show you a liar.
Prepare answers to common open-ended question. Tell me about yourself? Why should we hire you? What's your worst weakness? Google for more of these, as well as suggested answer approaches.
Be clear on why you want to work on a Cruiseship, in a way that both (a) sounds realistic, and (b) is in line with the companys requirements. I want to see the world, sounds more like someone looking for a paid-holiday than someone looking for a job.
Are you sure you're going to be ok with being away from home for 6 months at a time? Prove it.
Know the downsides. Are you ok with long hours? What is your idea of long hours? Does the cruiseline have a similar idea of long hours. Have you worked Long, or unsociable hours before.