Do preliminary research and decide on a thesis statement. This is the main argument of your essay. It shouldn't be a fact, but rather something which can be argued about Christopher Columbus.
Write an introductory paragraph that outlines the basic details about Christopher Columbus, and the time period in which he lived. Include any other background information particular to your thesis that is necessary to understand before you get into your argument.
Write your thesis at the end of your introductory paragraph.
Write three or more paragraphs that further your thesis on Christopher Columbus. The first sentence of each paragraph should introduce the piece of evidence you are going to write which proves your thesis. Include at least one statement of fact in each paragraph and explain how this supports your thesis.
Write a conclusion that summarizes your argument on Christopher Columbus. Restate your thesis at the start of the conclusion. You should not be including any new evidence in the concluding paragraph.
Add footnotes or end notes for sources that you reference in your essay. An essay on Christopher Columbus should be referenced either using the Modern Language Association, MLA, style or Chicago Manual of Style guide.