A family of Microsoft word processing software products for creating web, email, and print documents.
Although recent versions of Word do permit rotating text (usually in small amounts) 180°, this is really a project for which Publisher, if you have it, is much better suited. You can (indeed must) create text boxes that can be linked in any desired order (this is more difficult in Word) and easily arrange them as desired on a page. Find instructions for one version at http://www.brighthub.com/multimedia/publishing/articles/70811.aspx. If what you're wanting to do is have four pages on one side and four on the back, you'll need to modify these instructions.
A Google Images search for "8-page mini book" turns up many examples, such as http://www.scrapnframes.com/SITE_EN/SCRAPBOOKING/HTML_PAGES/Mini-Book-Origami-folding-Part1.html (which just shows the folding method). These general instructions are available at numerous sites, including https://youtu.be/21qi9ZcQVto