How to turn on auditing in your Office 365 tenant

Turning on auditing in your Office 365 tenant is a good practice that you should do if you are tasked with managing an Office 365 tenant.

Turn on auditing so that your users' and admins' activities will be recorded. I am referring to activities such as moving / deleting / renaming of files, folders, groups, emails, etc. Turning on auditing is a very good practice and can sometimes be a life-saver to an O365 administrator who is tasked with finding out the answer to "who has deleted this folder?".