Navigate to the Admin page of any of the Jazz Applications you wish to friend with your Jira.
Under Communication you will find the Friends page. In the upper right corner click on Add to initiate the dialog shown below. Fill out the required details and click on Next > once you are done.
Continue filling out the remaining OAuth Secret details for the new Friend connection:
Once you are done, click on Create Friend to finish the Friend Creation dialog. A green confirmation should show in the top of the dialog: