How do I zoom out using my Apple mouse?

TeddyDoe wrote:

That is by using computer commands. How about using the Mac mouse? It zooms in easily, but how does it reverse that?

I guess you didn't read the entire page…

"Use scroll gesture with modifier keys to zoom

After selecting ”Use scroll gesture with modifier keys to zoom,” you can press and hold the Control key while scrolling with your mouse or trackpad to zoom. Use the ”Zoom style” menu to choose from three zoom styles: full screen, split screen, or picture-in-picture."

In any case you scroll in the opposite direction.

See: How to zoom in or out on Mac

Just to be clear, you can't zoom out further than the actual size of the screen.