Effective communication relies on clarity and simplicity. Whether you’re showcasing a new software application, teaching a technical skill, or outlining a complex process, a well-structured step-by-step guide can greatly improve comprehension.. For example, consider the launch of a popular IT product—a cloud storage service—that was released without a comprehensive user manual.

You're right, starting with Word would be probably your best bet for creating a document, but there are other tools that will make other jobs easier. Also unless only one person is doing it, you'll want to have collaboration. Here's a link to some info on enterprise productivity tools of Office 365.

What would an instruction manual be without instructions? Here, you’ll break down the step-by-step instructions for using your product. Typically, you’ll break this down further to detail specific product features — making sure to prioritize those central to the product’s core usage.

To write a manual, break the process you're trying to outline down into easy, digestible chunks so that readers can follow along step-by-step. Also, make sure your manual follows a logical sequence so that readers can do everything in order without having to skip around between sections.