• Open System Preferences on your Mac by either selecting it under the Apple menu or clicking its icon in the Dock.

• Click Sidecar

The Sidecar options window will open. Here, you can decide where the Sidebar and Touch Bar will appear.

• The Sidebar contains buttons that let you open a keyboard, press the Command key, and other items that will help you perform tasks on your second screen. You can put it on the left or the right.
• The Touch Bar mirrors the functionality of the context-sensitive menu on some Mac models. It can appear at the top or bottom of your iPad display.
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• Click the box next to Enable double tap on Apple Pencil to quickly switch between tools, show a color palette, and more.

• Click the pulldown menu labeled Select Device to choose your iPad.

• Your Mac will automatically connect to the iPad.
• Select the Sidecar menu on your Mac to choose the iPad’s role. Select Use As Separate Display.

• Your iPad screen will get another desktop on it. You can drag windows between it and your Mac.

The Sidebar contains buttons to help you perform desktop tasks on your iPad.

• Tap the top icon to toggle showing the menu bar.
• The next icon will open your Mac’s dock on your iPad.
• The next four buttons mirror the Command, Option, Control, and Shift keys on a keyboard.
• The arrow icon lets you undo the last action you performed.
• Tap the keyboard icon to open a full keyboard on your iPad. You can use it along with the modifier keys above to navigate apps.
• Finally, tap the Sidecar icon to disconnect from your Mac.