Log in to your account and navigate to the In-Play link at the bottom of the homepage. Any event with a play icon beside it will be available to watch via Live Streaming.

If you set it to its maximum size on the site (using the 'expand' icon in the top corner of the video) and then zoom into the window, you can get it full screen  it will be slightly pixelated, but it's better than watching it small, I've found.