Basically you need a strong structure in your essays. Start of with a strong introduction and opening statement, which both display your thesis statement and/or opinion, if any. Briefly outline what you're going to be saying in the essay and then move on. Allow about three to four paragraphs explaining the topic.
Each paragraph begins with a concise topic sentence outlining the idea you will discuss. You will then prove your point with examples, quotes, dates etc. and further explain how these examples and quotes relate to the point which you are making. It is important in this to have a strongly grounded vocabulary and be able to use language to achieve an immensely controlled, structured and flexible piece of text. [Note: Do not start using big words just because you think the marker will think you are intelligent. Using the wrong words in the wrong contexts will only make you look more stupid]
Now, we move on to the conclusion. The conclusion summarises the points you have made regarding the text, and reiterates the thesis statement. Make sure you highlight and illuminate what we have learnt from the discussion with relevant references to the above paragraphs. Start by re-stating your main points using different phrasing from the introduction. Move from specific statements to more general observations - don't introduce new material. End with a statement regarding the consequences of your discussion - what have we learnt and why is it valuable.
Basically that is good template to follow if you want to create a well structured essay. Remember, although the structure has been set out, you do not need to follow it. With practise and experience, you will be able to manipulate the character of the language, play around with the text and create sophisticated and complex essays.
I hope this helps, and good luck.
