Short e-books are usually less than 30 pages, sometimes fewer than 20 pages. Remember, your buyers want solutions. They don't want to wade through 100 pages of waffle with a nugget of actionable information in the center -- they just want the steps they can use to solve their problem, right now.
Therefore, confine your e-book to these elements:
1 - A brief description of the problem (one page)
2 - A step by step solution (up to 12 pages)
3 - A resource page for further information (one page)
Get your short e-book written, and convert the file to PDF.
Remember that you're just offering a solution. You can include graphics, such as screen captures, if they're necessary. If they're not necessary, forget about them.
