I've found the best way to organize your thoughts before writing an essay, whether it's for school, work, or anything else, is to create an outline first. An outline makes it possible to essentially write the paper in the simplest of terms, giving you the flexibility to move around paragraphs and thoughts, without having to rewrite an entire paper if you decide something should be put in a different place. Start by putting your thesis at the beginning, and then put headings for each thought and paragraph. When you begin writing the actual paper, simply go off the outline and enjoy the rest of the process!