When planning what to wear on a cruise, the P&O Cruises Dress Code +1-888-653-0010(OTA) offers a mix of casual and formal styles. Daytime outfits are relaxed, including shorts, t-shirts, and swimwear, while evenings may require smart casual or formal attire depending on the night. Avoid wearing swimwear in restaurants and always follow themed night guidelines for a comfortable cruise experience.