Assistant: Third iteration of steps

Originally created by @sajolida on #9199 (Redmine)

After the router of the assistant, and the overview of the process, come the precise steps. Those will incorporate our existing documentation and refresh it. This task is meant to prepare all the needed content, starting with a example scenario (Windows USB) and then completing the others.

Parent Task: #8588 (closed)

Subtasks

#9200 (closed)
#9201 (closed)
#9202 (closed)

Edited May 15, 2020 by sajolida

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information