1. Read the sat essay prompt carefully
This is the step where many students go wrong. Read the prompt and with your pencil underline the main idea you need to be writing about. Most students who get low scores fail to read the prompt carefully. Don't be one of them.
2. Decide on a thesis
Now that you understand the prompt, choose one side of the issue presented. Your thesis must be the equivalent of a 'yes' or 'no' to the prompt. Don't be afraid to use the words of the prompt in your thesis. For example if they ask, "Are people basically good?" You can have a thesis that says "This essay will show that people are basically good."
3. Brainstorm 3-4 examples to support the thesis
Now that you have a thesis you can go in search of examples to support it. Quickly make a list of several works of literature you read in school or events you studied in history that support your point of view. Once you have these go on to the next step.
4. Create a short introduction that incorporates the thesis
You basically have the outline for your essay now. A thesis and a one sentence description of each of your examples. Now begin writing the introduction by saying a few words about the topic. Then one sentence on your thesis. It does not have to be anything fancy.
5. Write 3-4 body paragraphs
Now that your introduction is written support your thesis with the examples you generated in step 3. Make sure that in your paragraph you tell them what you are going to prove in the first sentence. Give a few details that prove your point in the next two sentences. And finally give a concluding sentence that tells how your example supported your thesis.
6. Write a conclusion that uses an analogy or metaphor to back up your thesis
The best sat essays end with an analogy or very brief anecdote that drives the point home. You can also make a prediction about the future. Whatever you do don't force yourself to come up with a brilliant conclusion. At the minimum you can just summarize the evidence you came up with to support your thesis.