Save a copy of the original, then compare one kind of change at a time: structure, factual content, or wording. A text diff will show exact additions and removals, but large formatting changes can obscure the important edits.
If the diff is noisy, compare smaller sections or restore consistent line wrapping before reviewing. For Markdown, inspect the rendered version too: a small syntax change can alter a heading, list, or link. After accepting changes, read the revised draft as a whole to check that the argument still flows.
The goal is to understand what changed, not merely to make every highlighted line disappear.
Akousa