To most people's minds, Hawaii conjures up images of luxurious tropical sun, beautiful beaches, mai tais, and flowered shirts. To astronomers, on the other hand, it represents dark nights, clear skies, and access to southerly constellations (and maybe some mai tais and beach time on the side). I've lived here in Hawaii (on the Big Island) for a few years and have met visitors from all over through volunteering at the Mauna Kea Visitor Information Station (VIS) and by giving a few tours through my work with the University of Hawaii. I'm occasionally contacted by amateur astronomers who are planning on visiting Hawaii and are interested in seeing the observatories or in doing some observing here. As a result I've compiled advice for visitors interested in astronomy and Mauna Kea in particular.