The first step in creating any kind of book in any form should be "have a story", whether this is literally a story (as in an original work of fiction) or a particular subject or another form of valuable information. The more expert you are in the realm of your chosen subject and the more straightforward you will find it to produce an eBook that has genuine value in the eyes of your eventual eBook readers. If the subject you are considering is one with which you are not so familiar then plenty of research will be needed to gain the knowledge required to make an effective final product.
Once you have your topic you'll need to break it down into sub-topics. If you're creating an informational eBook (which is probably) there will be subcategories which can be considered chapters within the book. If you are planning to create an eBook of, say, 45 pages which covers the entirety of a broad ebook kindle format subject, it is necessary to think ahead by identifying and naming the diverse issues you'll be discussing during your research. Each of these topics could become an entire chapter. The 45 pages can be broken down into 9 chapters comprising 5 pages each. Each of those sub-sections can be further subdivided into smaller chunks. One of the most important aspects to creating an eBook is working in small pieces at a time. To do this effectively, you'll need to have the book written out in detail prior to beginning writing. Each little section will be a building block for the final product.
My first foray into online commerce was nine years ago when I produced articles and eBooks about topics that relate to my profession as a musician. I am an oboist. I created an eBook about learning how to play an Oboe. This was put together from a collection of essays based on various techniques and problems that arise when performing the instrument. The finished ebook has continued to generate sales ever since. Being a topic where I was an expert helped enormously in the process of creating.
If you are of the opinion that creativity and writing is not your thing, it's possible to create an ebook of your own, but incorporating the writings of other people. A bit of research and you'll discover articles related to the subject that can be put together as chapters in a book, insofar as the article's are acknowledged as being written by the author. Articles published on websites of ezines can also be used as chapters in your book, so long as you reproduce the article totally unchanged and complete with the resource box, which includes any hyperlink. In fact, the authors are willing to use their work since their works (and their link) will be spread all over the world.
I hope that this article has given you a better understanding of the process of writing an eBook. As I'm sure that you see the process of writing or creating your own eBook isn't an overwhelming task however, it requires thought, planning and probably researching too. Even if you've never attempted to write something since you left school, don't be intimidated by the prospect. Everyone can learn!