Activating the User's public_html Directory with userdir

$ cd /etc/apache2/mods-enabled
$ sudo ln -s ../mods-available/userdir.conf userdir.conf
$ sudo ln -s ../mods-available/userdir.load userdir.load
$ sudo /etc/init.d/apache2 restart

and

make directory at your home folder named public_html as normal user($ mkdir public_html)

ref : http://kimbriggs.com/computers/computer-notes/linux-notes/apache2-public_html-virtual-directories.file