A good essay will always have a good balance between outline, evaluation and (if there's a 'stem' in the question) application. You need to make sure that you outline the theory/treatment, but that you also have a number of evaluation points. You should develop these points into PEE paragraphs - Point, evidence, explain. Each paragraph should consist of only one point and should include research evidence or an example, which should be explained clearly. Finally, a good essay could order these evaluation points into an effective flow and link each of these together and back to the question.