The process of writing a college essay is no different than the essays you wrote in high school. While the professors will expect a higher level of thinking, reasoning, and written skill, the actual process of laying out the essay is really about the same.
First, you will want to begin by brainstorming some ideas about your topic. Select the idea you think you can support. Take this idea and expand it into an outline. Show what questions you hope to answer and what points you want to make. This outline will also help you see what areas you will need to research in order to find support and evidence.
Once you have your outline finished, move on to writing the paper. Your outline will allow you to generate a thesis which encompasses the whole of your topic. In a college essay, most professors do not want you to list as you might have in a high school thesis. Your thesis should be a simply statement that will be proved by your paper rather than a list of the evidence they will see. Include the thesis in the introductory paragraph but reference it often to make sure you are staying on topic. Each body paragraph should focus on one point and one piece of evidence. The final paragraph should be a conclusion which wraps up the essay and also leaves the reader with something more to think about.
Once you have written your essay, don't forget to proof read. You may want to set aside the essay for a day or two and then return to proof read it. Trying to edit a paper you have just written is difficult because you mind will automatically see what you meant to say rather than what you did say.