New user--set up questions

I have used Ooma Office for nearly 4 years for my business.

I recently found the Ooma Office app for my iPhone 5S, and think it would be very useful. I would like to use it 100% for outgoing calls when I am not in my office.

What information do I need to set up this app? I set up Ooma Office years ago and may not remember all the details.

Is there a tutorial somewhere on the web?

Russell Barr MD