Any normal organizational pattern is acceptable. An overview of what you are going to accomplish in the answer should preface your analysis. Strive for readability and clear communication. Above all, observe the iron laws of paragraphing. Run-on paragraphs are difficult to read.
Every audience has style preferences.
Research tells us that workers soon learn to write in the style of their boss. Writing to answer academic test questions, in this grader's opinion, is different. Since style is also graded in the essay it is important to adapt your style to the grader's preferences. Margins should be no more than one inch on all four sides. I find 12 point font readable.