I once heard sailing described as the hardest outdoor discipline to learn. As a lifelong sailor I'd never thought much about it, but it's true: Other sports don't require the same breadth of technical and practical knowledge as offshore sailing. While you don't need a captain's license to charter your own boat, bareboat companies will expect at least one member of your group to be able to trim the sails, navigate (via charts, instruments, compass, buoy systems, and currents), and be versed in other aspects of basic seamanship such as anchoring, line handling, weather forecasting, heavy-weather sailing, as well as basic boat maintenance like diesel repair, plumbing, and electronics troubleshooting. However, big cruising catamarans, like the one we rented, are so easy to handle that most crew members can be neophytes. If you're an entire group of beginners, hire a captain.
It used to be that the only way to learn the ropes was to be born a blue-blood yachtie. Good offshore cruising instruction has, however, become more accessible in recent years. The American Sailing Association (310-822-7171; www.american-sailing.com) can put you in touch with more than 150 ASA-certified schools around the country that offer classes in bareboat chartering.
Captains for Hire:
Most bareboat companies have staff captains you can hire for $100 to $200 a day. They not only teach skills that will make you a more capable sailor when you're on your own, but also share inside information on the best sailing routes and places to dive and explore.