Practice organizing your writing. Before starting your written response allow 2-5 minutes to make an outline of your essay. Do not worry that the time is running, a good outline will save you lots of troubles and time while writing. The essay outline should include the major ideas for the paragraphs in 2-3 main phrases per paragraph, as well as some examples and supporting details. Do not write complete sentences, but some words and phrases that may help you follow that outline and add additional information to develop a well-organized and coherent essay.
A Note on Formality. In addition to having a particular kind of structure, academic paragraphs (and multi-paragraph essays, which will be topic of another lesson) are different from "ordinary writing" (such as letter writing) in that certain kinds of expressions are not allowed. For example, in formal essays, you should not use contractions such as don't or aren't. Instead, you should write out the words in full, for example, do not and are not.