Make sure that Bluetooth is turned on. Look for the toggle button in the Bluetooth Settings panel and confirm it is in the On position:

Push the button on the top of the WeDo to turn it on. When it appears in the list, click on your device. Unless you have renamed it, your device will be named LPF2 Smart Hub 2 I/O. Then, click the Pair button that appears below the name of your device in the menu.

When your device has been successfully paired, it will make a noise. In your Bluetooth menu, you will see the word Connected underneath the device name.