Developing learning materials for online learning can be a huge challenge. Learning materials should be designed under didactical and psychological considerations. By doing so, it is important to know more about our memory and especially about the limitations of our working memory. In the presentation, a short overview will be given about the information process, the limitations and essentials theory like the cognitive load theory. In consideration of these limitations, it will be shown how we can facilitate the learning process by multimedia learning. Several principles of multimedia learning will be presented, e.g. use text and pictures or instead of text use narration. These principles are helpful for developing diversified and motivating learning materials for students. Cognitive load can be reduced and the information process will be better supported.