Learn by doing. I see and I remember. Rely on previous experiences. We all have a conceptual mental model of the world that we have learned and that has evolved over time. When confronted with new situations and new tasks we use this mental model so that we do not have to re-learn and understand every new situation.
People differ in how they learn.
You have to try to think about the users' knowledge and perspectives. Seven deadly temptations. Design for technology rather than for the user. We as computer scientists tend to become enamored of the technology. We think that technology is good for its own sake.