With the objective of transmitting high level skills to clean the interior of a combine harvester, a method to create a new cleaning manual based on empirical knowledge was developed. Firstly, in this method, the knowledge of expert workers is extracted from interviews and from watching videos of them performing cleaning works. Secondly, the extracted knowledge is summarized in a table and, finally, written in sentences with corresponding figures. To verify its effect, a cleaning manual was created based on the developed method and a cleaning test conducted. As a result, the amount of residual grain remaining in the machine after cleaning significantly decreased.