@Grantler’s advice is radical and should be considered as a last resort because you’ll lose notes, cross-references, tables, frames, pictures, indexes, … with the risk of introducing carriage-returns at end of every line causing them to become afterwards paragraphs.
The favorable case is your document is thoroughly styled. In this circumstance, all you have to do is review your styles. Take special care on possible manual direct formatting which may hide your changes.
The case were your document is exclusively direct formatted is not so bad. Define first a set of styles: paragraph styles for general aspect of paragraphs (content, titles, outline, …) and character styles for the intra-paragraph variants. Don’t forget page styles if needed (cover pages, ToC, indexes, chapter and possible first chapter pages). Then keep a copy of your book so that you can display side by side the original and updated versions. In the updated copy, select all text (Ctrl
+A
) and clear direct formatting (Ctrl
+M
). Now, apply a paragraph style paragraph after paragraph. When some words inside a paragraph need highlighting of some sort, apply a character style to them.
The worst case is when you have a mixture of styling and direct formatting. It is likely then that your styles are not consistent. You can’t rely on them to elaborate a new set. Make an unformatted copy as previously and try to infer the needed styles. Always compare copies when proof-reading.
The task is tedious, there is no way out but it is an immense opportunity to discover the power of styles. To cheer you up, a personal note: many years ago, I was under a deadline to write a technical notice (which ended up in the 150-200 pages range) and it was my first contact with a document processor. I took the time to study the available features to see how to tackle the task in a reasonable amount of time. It was in fact an upgrade from a document composed on a mainframe, using macros to typeset text (something in the spirit of LaTex). Cute styling allowed me to achieve the job in 15 work days.
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