Open Outlook 2013/2016 and click File 

Click Info, then Account Settings, then Account Settings again.

Click Email Tab and then click New...

Type the name of the shared mailbox in the Email Address field.  Then click Next.

It will search for the settings, this step may take a minute or two

It will then ask for the credentials for the account.  Replace the shared email address in the Username Field with your Park ID number followed by "", then enter your Park password and click OK.

It will then complete adding the shared mailbox.

Click Close.

Finally, you will need to completely Exit Outlook and restart it.

You may wish to add a signature for your Shared Mailbox that is different than your personal signature.  The link below will show you how:

How To Add A Signature To A Shared Mailbox In Outlook