the easiest way is to buy a Google Chromecast.
Plug it into an HDMI port on your tv than you can cast Stan from your phone.
Sorry I didn't understand from your post you wanted to use the unmetered data from your mobile plan.
There has been a lot of discussion regarding this.I consider the safest way if you have an Android phone is Miricast as this just casts your phone screen to the tv. Again the Miricast dongles are cheap on eBay but depending on your phone screen resolution the picture may not be as good as Chromecast.
Worth a try for around $20 and then check your data usage.