Carry a flashlight. It gets really dark on the Big Island once the sun goes down. There are very few street lights and the ones we have are all pointing down, so there is no interference with the beautiful night skies and the observatories on top of Muana Kea.
Take water with you when you go on outings. Keep hydrated.
Reef sox or water shoes are always great to have along. Everything is an adventure on The Big Island. You might be on a hike and find a stream or just navigating a lava shoreline.
Take a jacket or sweater where ever you go! It might be warm and sunny at the beach and within 15 minutes you might be in a tropical rainy area. The temperature can change dramatically the higher up you go.
Wear a smile....everyone is happy.
Cell phones work in most areas.