Reading aloud is often an essential part of the writing process that often goes unmentioned. For example, as you're writing an essay, you may choose to read what you have written aloud while writing it, or you may opt to do so once you've finished. This is actually very useful regardless of whether you are writing a first draft or your final submission.
I completely agree with Stephanie's comment in regards to hearing errors crystal clear as one reads their essay aloud. Another method you could use is reading your written work to either a friend, parent, sibling, etc. You could easily see if your essay makes sense by doing so. It is a method that has assisted me when I was in college, and I feel like it works very well for most people.