Oceanography is a multidisciplinary science that deals with the physical, chemical, geological e biological aspects of the marine environment. As most of the sciences, oceanographic research relies heavily on sampling procedures, which can be rather simple, as obtaining a water sample at sea surface, or very complex, as bringing an uncontaminated sediment sample from hadal regions (up to 11,000 m deep) to the surface. Despite the sampling operation complexity, it is of primary importance the use of the adequate instrumentation, as well the expertise of the instrument operator. Ideally, the operator should have a good knowledge of the technical characteristics of the instruments themselves, as well as the correct procedures for their operation. In addition, he should be well acquainted to the ship equipment employed in the deployment, operation and retrieval of those instruments, including cables, winches and cranes. Only if these aspects are taken in account a reliable and safe operation can be attained. In this way, this guide was conceived as a basic reference for researchers in their on-board operations, although certainly being useful for a wide range of outdoor activities. It was based on the authors years of experience in field work onboard research and fishing vessels. It includes notions on nautical cables, onboard load handling equipment and hardware, basic ropework, basic net weaving and repairing and a nautical glossary.