Step 1: Apple menu
Click on the Apple menu at the top of your screen. Then click on Software Update, and when the new window appears, click on the Show Details button to reveal the window in the next step.
Step 2: Check and install
You can now check the update. It’s always good to know what you are installing. Click the Install button and then you will be told if a restart is required. If so, just click through the prompts and wait for the update.