This is primarily for women since I am one, but I will advise men to take a jacket, dress pants and shoes (and socks) and a tie.
Cruise Casual--shorts / capris and T-shirts, blouses, flip flops
Around the pools of course, swimwear and cover-ups
Buffet type food locations: swimsuits and cover-ups are fine
Table service food locations: no tanks, swimwear
Cruise casual, unless designated
3 out of 7 nights were dressy for us:
(1) Captain's Gala, the most formal--cocktails and hors d'oeuvres, photo shoot with the Captain and crew in their dress uniforms
(2) Dinner at Palo restaurant
(3) Another evening that was designated as semi-formal
I took one long dress with two different shawls and jewelry to change them up.