What you need to do is to register your Google+ page as a site owner of your blog. For things like this, Google uses e-mail addresses, because e-mail addresses can be guaranteed to be unique. And as it happens, your Google+ page actually has an e-mail address, which is a nonsense e-mail address, but we can use it all the same.
First, go to your YouTube account and find the advanced settings. You do this by clicking on your channel icon at the top right of any YouTube page, then on “YouTube settings”. Under “Account information”, next to your channel icon and just below your username, is a tiny link labelled “Advanced”: click that.
On the page that then appears, the first entry under “Account information” should now be a cryptic e-mail address ending in @pages.plusgoogle.com; highlight it, and then press Ctrl+C (Windows) or Command-C (Apple) to copy this address to the clipboard.
|This is a nonsense e-mail address, automatically generated just to make the whole linking process work.|
Now go to Webmaster Tools, where you should see your blog listed. Click on it to bring up the “Site Dashboard”, with various statistics and information regarding your blog. To the right is a gear icon: click on that to open a menu and choose “Users & Site Owners”.
|Did you even know all this was there?|
This takes you to a page that lists all the owners and users of your blog, which will most likely just have your e-mail address listed as an owner. We want to to add to that list the address you currently have in your clipboard.
The temptation here is to click on the big red “Add a new user” button, but that would be the wrong choice. Instead, click on the link that says “Manage site owners” — we’re adding an owner, not a user.
|Don’t click the button! Click the text link next to it.|
Now you should see a list of verification attempts, and below that a list of site owners, with your e-mail address listed. Below that, a button that says “Add an owner”, which you should now click. This will open a little text box which will accept an e-mail address. Click in that box to put the cursor into it, and then press Ctrl+V (Windows) or Command-V (Apple) to paste the e-mail address you copied earlier into that box, and click “Continue”.
|Bear with me: we’re nearly done.|
You should now see this new e-mail address added to the list of verification attempts (marked as “delegated by [your e-mail address]”) and the list of verified owners.
It might take a few minutes for this change to filter through to YouTube, but you should soon be able to link to your blog in an annotation.