Download Mango Display App from the App Store on your LG Smart TV (available on models 2018 and newer)
Open the Mango Display App, it will provide you with a 'Display Device Code'
Visit app.mangodisplay.com on any browser (phone, tablet or computer). Register and log in.
Once logged in. Click on 'Add New Display'
In the next screen, select the Mango Display LG WebOS TV App
In the next screen, name your Mango Display (Living Room, Kitchen TV, etc.) and click 'Next'
Enter the 'Display Device Code' that is displayed on your Mango Display App (Refer to step #2 above). Click Finish.
Done! 🎉 Your LG TV is now connected and the layout can be configured as needed.