In small- and medium-sized enterprises (SME) training requirements differ widely and can hardly be covered by broad training programs. For this reason these SMEs heavily rely on internal company training and informal knowledge exchange between co-workers to effectively use pre-existing resources like highly specific expert knowledge. To this end, professionals need to be trained in efficiently communicating their subject-specific knowledge as well as in realizing informal learning opportunities. Hence, in the postgraduate training program "Designing workplace learning and knowledge exchange" (aquwa) professionals are taught the necessary didactic competencies. The training takes place parallel to work over a 12-week period in a blended e-learning format. Modules 1 and 2 deal with principles and methods of knowledge exchange. These principles and methods are further elaborated in Modules 3 and 4, culminating in participants' independent development of an informal learning opportunity at the workplace. The evaluation of the training shows a great acceptance of the course design as well as a significant learning gain over time. Most of the participating professionals recognised a successful transfer of the gained competencies into their workplace. Based on participants' remarks suggestions for online-based postgraduate education courses are provided.