Open System Preferences and click Bluetooth. Choose to turn it on or off.

1) Open System Preferences.

2) Click Bluetooth.

3) To enable Bluetooth, click Turn Bluetooth On.

To disable Bluetooth, click Turn Bluetooth Off.

Outcome

You have turned Bluetooth on or off on your Mac.

TIP: You can check the box next to Show Bluetooth in menu bar to turn it on and off from the menu bar.

To enable Bluetooth from the menu bar, click the Bluetooth icon in the menu bar and move the switch to the "on" position (to the right).

To disable Bluetooth, click the Bluetooth icon in the menu bar and move the switch to the "off" position (to the left).