To design and develop effective computer-based training screens, take advantage of visual psychological impact. Treated as a grid, the screen has high and low impact areas. Position the elements of the message to take advantage of these. Use visual cues to create planes and layers for emphasis. Decide on the content types which make up your message. These include concept, principle, process, procedure, and fact. Build screen sequences to make the purpose of the content clear to users. Add application level questions to keep users involved.