A GOOD first aid kit. Mine always contains basic bandaging supplies (gauze, tape, regular band-aids, waterproof post-op bandages, small scissors, duct tape– which works for boards as well as skin in a pinch).
Neosporin/betadine/some other antiseptic and antibacterial. Alcohol and hydrogen peroxide for cleaning out bad cuts and ears. Some people swear by paw paw cream for reef cuts and sunburn. Also don’t forget the Tweezers for pulling bits of foreign organisms (reef, sea urchin spines) out of your body!
I always bring some sort of tiger balm, salonpas, or Doterra Deep Blue cream to massage into sore muscles. It makes me smell like a 90-year old Asian grandma but feels SO GOOD on my tired, overworked shoulders and lats.
Toiletries. Sunblock & Zinc
I always use reef-friendly tinted 30 SPF all over + Surf Yogis zinc on top of it for my face, and make-up removal wipes to take off all the sunblock and zinc and avoid breakouts.
I usually just bring shampoo and conditioner, figuring shampoo is basically soap. I make sure that all products are reef-friendly (paraben, oxybenzone, and octinoxate free). And (of course) I bring a deodorant. PLEASE! For all our sakes!
I also bring good, cold-pressed organic virgin coconut oil as my all-around moisturizer, plus it’s super-functional: its antibacterial qualities help with minor cuts, it soothes sunburn, you can put it in your bulletproof coffee, it helps to save your sun and saltwater-fried hair, and it can be a good massage oil in a pinch.
Oh yeah…
Bug spray/wipes – again, people who traveled to tropical destinations know..
Last but definitely not least
Passport – or you’re not going anywhere! Make sure you have fulfilled any visa requirements/paperwork you need in advance. Electronic copies of your travel itinerary and passport that are accessible offline on your phone.
TRAVEL INSURANCE! Make sure that you have all the details of your health insurance and travel insurance policies with you – a friend/trip organizer should also have a copy of all the above documentation.
And… you are set! Have a wonderful trip, hopefully, confident you have all of the things and only the things you need!