Proofread the work. Do not jump right away into a copy editing task without first proofreading and becoming familiar with the written text. The manuscript must first be read from start to finish. This gives you a chance to observe any obvious grammatical or punctuation errors, as well as any other mistakes in the manuscript.
Correct grammatical and spelling mistakes. Once you have read through the work, go back and begin reading at the first line. Correct any grammatical errors, such as run-on sentences or redundancy. For example, some writers might use "and also" together in a sentence; however, this redundancy should be avoided and only one word used. It is also important to check for any spelling mistakes. If a publisher finds a manuscript filled with grammatical and spelling errors, the work will be rejected. It is important that a writer is literate throughout his manuscript.
Check for continuity. It is important a manuscript is consistent. For instance, if you are copy editing a manuscript for a novel, and the author states in the first chapter that the protagonist is 30-years-old, but in the following chapter he is 40-years-old, this lack of continuity must be corrected.
Check for facts and answers. When editing work, a copy editor must look for answers to questions, such as "Is this story consistent?" or "Does this story come full circle?" and "Is there any missing information or holes in the story?" It is also important to make sure the facts are correct, such as historical dates or the location of a town and city.
Check punctuation. Punctuation errors are some of the most common mistakes writers make. Many times, commas are misplaced or missing, quotation marks are used incorrectly and exclamation points are unnecessarily placed. For both writers and copy editors, it is wise to keep a grammar book handy in case you are unsure about the use of punctuation.