Think of your audience as you are designing your ebook. If you are creating a children's book, you will need to include pictures that will captivate the young readers. If you are writing a tutorial, you may need to add instructional diagrams.
Set the margins to one-inch throughout to make your ebook easier to read on the computer.
Use a legible font available on a majority of computers to help readers with disabilities.
Use consistent styles, color-schemes and fonts for the section headings and body of your ebook.
Add a table of contents to chapters and sections of the book. Insert bookmarks and hyperlinks to resources that your book references.
Include keywords, description, author and copyright detail. If you are using a web editor, you can add the following code between the HEAD tag of your HTML file to include them:
<META NAME="keywords" CONTENT="keyword1 goes here, keyword2 goes here">
<META NAME="description" CONTENT="information describing your ebook goes here">
<META NAME="author" CONTENT="the writer's name goes here">
<META NAME="copyright" CONTENT="your copyright information goes here">