Cruise to Alaska - what to wear, bring

Hi girls,

I am going on a cruise to Alaska at the end of the month with DH's family. I am really excited, but I have no idea what kind of clothing to bring. I have heard mixed reviews on the weather. Is it warm enough to wear open-toed sandals on the ship? What about daytime wear ?? I am not really an outdoorsy person, so I don't have much 'gear' if you know what I mean.

Help!