Adding a colleague's e-mail so that they receive sales notifications

I would like to add another email address so that it can receive notifications of sales and related actions.

How can I do it, looked everywhere (I think)

As far as I know, you need to add them as a user and can pick "store manager" in the permissions. That is how we did it. 

Thank you for your response, without trying to sound stupid, how and where do you add a user?

The notifications etc are going to our login email which is different from our contact/google account email address.