What is the secret

[Zachaios-malganis (Zachaios)]

Courtesy of a 25 second google search:

How to Restore Classic UI in World of Warcraft | WowVendor

Also:

How do I get my old ui back

I hate the new ui set up I’m trying to move things and I’m getting frustrated I don’t use add ons and loved the ui because it was simple to understand I HATE the new set up.