To publish your Vidpresso Stream to your YouTube account you need to first find your Streaming Server URL and Stream Key. Here are the easy steps to find those.
Log in to your YouTube account and click on your avatar in the upper right corner. Click on 'Creator Studio'
On the menu on the left-hand side click on the "Live Streaming" tab.
This will open a main 'live stream' interface.
The Server URL and Stream Key are on the bottom of this page under the "Encoder Setup" heading.
Copy this link and the Key into Vidpresso. Details are here in this article.
Leave this page open. Once you have started your live stream in Vidpresso, You'll want to come back to this YouTube Live Stream interface to make sure your title and description are ready, you'll also be able to see the YouTube comments on this page.