Editing is what you begin doing as soon as you finish your first draft. You reread your draft to see, for example, whether the paper is well-organized, the transitions between paragraphs are smooth, and your evidence really backs up your argument. You can edit on several levels: content, overall structure, quality of evidence and analysis, clarity, style and referencing. Make sure you finishing all your editing before you more onto proofreading.
Proofreading is the final stage of the editing process, focusing on surface errors such as misspellings and mistakes in grammar and punctuation. Proofreading should only be undertaken after you have finished all of your other editing revisions.
Editing, for example 1000 words, usually takes about twice as much time as proofreading.
This is how our proofreading and editing services compare: