Turning Off Notifications While Presenting [duplicate]

• Simplest way is Option (⌥) + Click Notification Centre button; top right corner. It should make the NC dim. ⟶
• Open NC then go to Today tab scroll up, it should show Do Not Disturb button, just turn it on.
• @Buscar웃 said you can also turn on the keyboard shortcut in System Prefs -> Keyboard -> Shortcuts.

You can either use the System preferences- Notifications- and use one of the options there that suits your need to turn OFF.

Or you can use keyboard shortcuts, in the syst pref- keyboard- shortcuts, and assign a short cut that will turn On/Off the Notification (keyboard is faster) but you have to remember the short cut.

There is also this method https://apple.stackexchange.com/a/154563/46541