To activate Zoom on Mac:
1. Click System Preferences > Accessibility > Zoom
2. Choose either or both of the following options:
- Use keyboard shortcuts to zoom: when checked, you can use the listed keyboard shortcuts to zoom in and out.
- Use scroll gesture with modifier keys to zoom: when checked, you can use the modifier key (Control, etc) while scrolling with your trackpad or mouse to zoom in and out.
3. Check Smooth images to make content appear smoother when zoomed in
4. Choose a Zoom Style from the drop down menu
See the video below for a demonstration of activating Zoom on a Mac.