How to integrate/combine the process of writing a book with making money?

I want to write a book. But you know, writing a book requires a long time and I have no idea whether or not my book will sell out after it is written out. I want to make money, to have my own business. How can I integrate/combine the process of writing a book with making money?

Books alone rarely make any money. A book needs to be part of a bigger strategy that uses a blog, a book and other venues to attract customers to your product or service. If you don't have a complete strategy that goes beyond the book, then book sales will be lackluster.

As NetTecture mentions, you either have to be famous or have a compelling topic in order to really make any money just off the book.

I don't want to discourage you from writing since it's a wonderful experience to write a book (at least it was for me). Just realize that it takes a tremendous amount of self-promotion and marketing to generate book sales.

You can not. Point. Unless the topic of your book (which you say nothing about) is really interesting to many people (which it most likely is not). And even if it is, who cares about you - as in: you are not famour or so that people take an interest in you already.