Essay is nothing but a series of paragraphs, each dealing with a distinct aspect and so arranged as to from a connected whole. In a word, an essay is an exercise in original composition, intended to test the expression of one’s ideas in suitable words.
Writing is a creative process, and like any other creative process it involves some experimentation, especially when you want to write a good essay.
There are many types of essays used for different purposes. Students gain experience in writing different kinds of prose that can be useful in their future careers and day to day affairs. Therefore, students should develop a versatility in their essay writing styles, so that they can face any English essay assignment confidently. Some common types of essays are:

• Argumentative essays
• Persuasive essays
• Compare and contrast essays
• Cause and effect essays
• Expository essays
• Literary analysis essays
• Character analysis essays
• Literary critique essays
These directions are written for students to follow when choosing a topic, creating a basic outline, and writing the essay.
• Assess what the essay requires
• Think about what you want to say
• Plan the essay by listing headings or key points
• Write the first draft
• Read and refine the draft
If you feel it is necessary, after writing your paper you can go on to get help from an editor or proof-reader. Some second-language speakers do this to improve the quality of their grammar and spelling. Other students might use an editor to improve the general flow and structure of their paper, or to make sure that they have covered all of the important points in terms of the subject they are writing about.
Remember that an essay is not complete once you have written the first draft. It is essential for you to read it through at least once or twice, making corrections and improvements.
My advices : show your knowledge of the subject you're writing about. Do it by demonstrating that you know the primary source text(s) well, that you can choose appropriate examples and fit them into their contexts. Do it by showing that you can analyse those examples clearly and coherently. Do it by integrating this analysis with the opinions of other critics. The revision of the essay which should be thorough and critical so that any stake which might have crept in, should be rectified.