You need to unlock your purchase on the webpage on your computer. To do so, click on the “Already Ordered?” link beneath the purchase button and type your email / password you received in the purchase confirmation mail from firstname.lastname@example.org. Full Unlock guide here. One you can access the show you can connect your computer to your Smart TV with an HDMI cable. Note: Up to 3 unlocks of the event are allowed.
If you have Chromecast please read this
If you have an Apple TV - this