[header] How to write an introduction to a book [title] Summarize or outline the book. [step] If you have an outline, pull it out to use in your introduction. If you don't have an outline, go chapter by chapter and write a short, paragraph-long summary of each chapter as your outline. 
[substeps] Think about your main ideas as you are writing notes for your introduction. Sketch out the overall themes of your book, so you have them ready.