Read the question and think of your top 3-4 factors which explain the question. Have a clear line of argument throughout the essay. Introduce information relevant to your essay (this can include statistics), analyse the significance of this information, then explain how this proves that your argument is valid (this is known as point, analysis and explain). You can also use historians quotes to back your argument and analyse conflicting historians views to demonstrate that you have a wide knowledge of the essay topic. To conclude, you should give a brief summary of your factors and how they show that your line of argument correctly answers the question.