Wait, the user just said "put together a useful guide". They didn't specify their OS or knowledge level. So maybe assume a Windows user with basic tech skills.
I should also mention that sometimes RAR files can be password-protected. If the user has the password, they need to enter it during extraction. If not, it's a problem. But maybe that's a scenario worth covering briefly. Roughman Injection.avi.rar
Another point: if the user is on macOS, which file archiver to use. 7-Zip has a version for macOS, but some people use The Unarchiver or Keka. Maybe a quick mention there. But since the query is in .avi.rar format, and the user might be on Windows, perhaps focus on the most common OS, which is Windows. Wait, the user just said "put together a useful guide"