There are basically three ways to be a working musician on a cruise ship. The way I’ve gotten into it is as part of the ship’s show band (sometimes referred to as the orchestra). In this position, your main role is to play themed production shows with dancers, singers, etc. You might also play jazz combo sets with a stripped down version of the band, as well as backing up the guest entertainers. As a show band musician, you’ll share a small room on one of the crew decks.
Option two is to be hired on with your band. You’ll probably be hired to play in a specific style – lounge, caribbean, blues, string music – and you’ll need a sizable repertoire. You’ll also need to be well rehearsed. Cruise music is primarily intended as entertainment, not art, so whatever you’re playing needs to be tight and clean.
The final option is to be hired solo (also called “guest entertainer” or “variety entertainer”). This includes a lot of different positions, including solo guitar/piano acts, dancers, singers, magicians, jugglers. You either perform solo (probably classical guitar or piano – they’re not ready for solo bass 
), or the show band can back you. Compared to working in the show band, guest entertainers make more money, work less hours and days per week, and get a larger room of their own on a passenger deck.
