Disclaimer: To use a Twitch stream on your page you have got to have https enabled for your domain. If you haven't got an SSL Certificate yet or you don't know what that means please contact our support and we will set it up for you.
Click on the "share" symbol underneath the Twitch video you want to integrate.
In Onescreener go to "Content" and select "Sound / Video"
Paste the link you copied before in the textfield and click on save