You won’t get extra time for editing your TOEFL essay. You will get only around 30 minutes and during those 30 minutes, you have to organize your essay, type it on the computer and edit it. Don’t write right until the time ends. This will leave no time for editing. If you submit your work without editing, you are unlikely to get a good score.
An common mistake that students commit is that they focus too much on the number of words. Your TOEFL essay should have at least 300 words, but try to write more than 350 words.
You should develop a habit of reviewing your work within the time limit. While practicing at home or with a tutor, try to complete your work within the time limit. If you take longer while you practice, you won’t be able to complete the essay within the stipulated time during the actual test.
You should also have a decent understanding of the kind of errors you are likely to commit. All writers make certain mistakes that are peculiar to them. Identify your weak areas. For some students, prepositions are the biggest problem. Others may have difficulty using verb tenses or relative clauses.
While practicing in your class, identify the mistakes you normally make. Look for these errors while editing your actual TOEFL essay. This way, you will be able to eliminate more mistakes.
While editing your work, don’t read quickly or passively. Don’t expect your mistakes to reveal themselves. You have to find them. This wouldn’t be possible without active reading. Read your work quickly but actively. Don’t skim.
You can’t perhaps edit every possible error because you are unlikely to have the time. You should devote the majority of your time to writing and set aside one or two minutes to review your work. However, if you manage to catch some basic errors during these few minutes your writing will improve greatly.