How to add HTML title tag in on a link in Blogger?

Since title tag have importance in SEO but, however you can not add title tag in Blogger post while being in compose mode, so you need to edit HTML. The anchor text (the text on which link is suspended) and title tag (appears when a user hover on link) are two major text which describe the page (to which link points to) more than the page itself, so you should add title tag to images, links, flash and other media because it gives search engine to crawl content from each of them.
So, as I said that you need to add HTML attribute inside the link. For that you must know how a link tag looks like.

To add title tag on a link, you must first create a link using normal method in Blogger, let me clear that while creating a link in Blogger, the text you write in Text to display field is actually anchor text. So after creating a link toggle to HTML mode from left top corner and press Ctrl + F (in windows) to search. Search for the anchor text you wrote and all you need to do is add the title attribute like I've done below:

Without title tag

<a href='http://moz.com'>MOZ</a>

With title tag 

<a href='http://moz.com' title='The Moz Blog'>MOZ</a>

When to use title tag

Title tag provides additional information about the page link points to, it is not necessary to add title tag in all cases nor you should add title tag same as anchor text. Title tag can be used like this:

<a href='http://about.me/hamzadhamiya' title='More about Mohammad Hamza'>Mohammad Hamza</a>

Now here title tag describes that what will be on the page the link points to.Or you can use the title tag for some design reasons like the below one:

 As you can see it provides a full title where it was cut due to some design reason. Not only design or usability but title tags are important for SEO too. So make sure to add relevant title tags on the links.