Convert to Publishing Format
At this point, you have a number of HTML chapter files ready for publication and a cover image. You need to get all this together into a package in a format for publication. I use the freely available program named Mobipocket Creator for that procedure.
To build the publishable book file, make a new project in Mobipocket Creator. This step creates a .opf file in the a subfolder of the My Publications folder in My Documents. Subsequently double-clicking that file starts up Mobipocket Creator with your project loaded.
Add to the project all the chapters' HTML files in the order in which they should appear in the book. Add the cover image to the project. Open the Table of Content view and fill in the form telling Mobipocket Creator which HTML tags (h1, h2, etc.) to use in the table of contents. Click the Build button. Mobipocket Creator builds a file with the filename extension .prc. That is your publishable file.
Preview the Book
As you build your book, you should preview it frequently, particularly the technical content. While you have only html to work with, before converting to publishing format, you can preview the book in your browser, which gives a rough preview of how the content is formatted. But your CSS and HTML code might include features that Kindle does not support. Eventually you need to see the real thing.
Amazon's Digital Text Platform includes a Preview feature that displays the book in a webpage popup window. To use that preview, you must open a new project, and upload the book's content. This process is time-consuming, and the preview does not accurately emulate Kindle's display device. There is a more convenient way. Downloaded the free Kindle for PC application to preview your work.
Install the program. Then double-click the .prc file that Mobipocket Creator created with its Build command. That runs Kindle for PC with your book open. This is a reasonable facsimile of the book as Kindle will display it. The illustrations are crisper and in color, however, and the display itself has more flexibility with dimensions, so you should do the final preview on the Kindle itself.
To preview on the Kindle, connect it to your computer with its USB cable. It looks like a disk drive on your PC just as cameras, memory chips, and MP3 players do. Copy the .prc file to the Kindle's Documents folder. Eject the Kindle and go to its Home page. Your book is now among the other books stored in your Kindle, and you can preview it.
Check out the illustrations and code text to ensure that they display properly.
Publish your Book
Publishing a Kindle book involves uploading the book's contents to Amazon's Digital Text Platform website.
You must set up an account and be logged in. There is no charge for the service. You create each new project from this site. You upload the book's content file and its cover image to the dashboard. After you set a price and assure Amazon that you have rights to the book, you can publish it. A day or two later the book is available for readers to download from Amazon's Kindle Store website. Amazon keeps an account of your sales and sends you some money from time to time.