18 year old work experience/job on cruise ship?

Hello,

I'm Athena, an 18 year old girl as of May 2014. After I finish high school, I really want to spend a month or two doing work experience or taking a job on a cruise ship. I've been on many cruises and have observed staff who work there.
I thought work experience because they are more likely to take me if there's no salary?
I know it's not as glamourous as it seems, but I can handle working 12-16 hours a day. I'm physically and mentally fit, fav hobby is mixed martial arts, kickboxing and yoga.
I can fluently speak English, Cantonese, Mandarin and intermediate in Spanish.

I'm not sure what position to apply for though. I have experience with kids from babysitting and work experience at childcare centre, tutoring them piano, etc.
I want a waitress position but not sure they would accept a 18 yr old with limited experience.
I could play cocktail piano in the lounge, but it offers limited interaction with other staff.. and perhaps my repertoire isn't wide enough.

Thanks!! :) What can I do??