While there are various ways to do this efficiently, my main tip would be to stay clear, concise, and most importantly consistent throughout your essay. What I found to be a successful method when writing history essays is to separate each paragraph, or each argument/idea, into three sections. First, you could start with historical narrative. This allows you to explain the relevant facts that contextualize your point in about two or three sentences. Then, provide one source, or school of thought, that has interpreted these facts in a certain way. You could do this by citing a historian that has researched and published material in this area of knowledge. In history essays, however, it is extremely important to provide a counterclaim: find a historian or other source that disagrees with the initial claim. Once you have done that, you have set yourself up well for critical evaluation. What are the implications of these two claims? What can you deduce from these statements?