Prior to sending your manuscript out for editing, preview it for “tightness” with a critical eye to detail. Do you have a general outline for your book? Go back to that and review it then look at your work chapter by chapter to see how well your work sticks to the original outline and premise for the work.
Go to the first chapter of your book and find your thesis statement. It should be relatively obvious and in the very first paragraph of your work. After you find it, underline it. Then go back in the rest of the chapter and highlight ONLY the parts that are directly related to your thesis in that chapter. How much of the work is thesis centered? How well do you communicate the supporting details to prove or expound on your thesis? How much fluff is there?
The fluff has to go! Tight writing requires an economy of language and a straightforward approach to the topic discussed. Sentences that are more than 17 words should be re-evaluated for unnecessary verbosity. Remove any fluff or unrelated material (save it for another section of this book or for another book – even for a handout or workbook when you start speaking in public on your book).
Then take what is left and organize it according to the outline you used earlier to craft your work. Turn some of what you wrote into bullet statements, some into supporting paragraphs, etc. Your work should fall more naturally into place if you do this. The writing will be more cohesive and the entire work will be logical and easy to follow.