GitHub Project Page on Subdomain of GitHub User Page

I have  been wondering on how to put GitHub Project Page into subdomain of my GitHub User Page as no detailed instructions can be found around. In case you don't understand what I want to achieve, say I already have my GitHub User Page (hansnewbie.github.io) to use custom domain to hansadrian.com (you should follow the guide at http://davidensinger.com/2013/03/setting-the-dns-for-github-pages-on-namecheap/ - I am using Namecheap since it is cheap, as the name suggests). Now, I would like my GitHub Blog Project Page (hansnewbie.github.io/blog) - which is automatically redirected to hansadrian.com/blog - to use custom subdomain of blog.hansadrian.com.

Namecheap for GitHub Pages

So I was looking into custom domain for my GitHub Pages and I asked my friend which custom domain service he is using. He is using Namecheap¹. I bought the domain and was configuring it when I was lost O_O because I am new to this and GitHub help does not have specific instructions on this. I googled and found http://davidensinger.com/2013/03/setting-the-dns-for-github-pages-on-namecheap/.

Hopefully it will work :)

Update:
Hoo Haa! It works :D Go visit my site! www.hansadrian.com

1. Affiliated links. If you wish to register without referral, go to namecheap.com :)