>You have to write the book while continuing working. Writing tech books does not pay the bills. When I wrote my book, Whil asked me, "Why do you want to write this book because you won't make any money from it?" My response was, "My mom can put it on her coffee table and be proud of me." I figure I make less than $3/hour writing my book.
What kind of hours did you put in and how long did the book take to complete? Plus did you get guidance? Idea for a book is something very abstract than planning the flow and chapter contents.