Congratulations on the testimonial! Adding a new one to your website is simple. There are 5 simple steps:
The title can be whatever you like as it's only seen by you in the dashboard, but it should be easy to tell testimonials apart. I recommend using the name of the client along with a few words from their testimonial. For example: "John Doe - Law Firm did such a great job..."
This way if you get multiple "John Doe" testimonials you can easily tell which is which in the dashboard in case you need to edit or delete one of them.