In order to enable the user-specific public_html directory open up a terminal and switch to the apache module config directory:

cd /etc/apache2/mods-enabled

If you list all the files inside this directory you’ll notice that all of them are actually symbolic links. To enable mod_userdir, which is the module you’re interested in, you’ll have to create two symlinks to the relevant files:

sudo ln -s ../mods-available/userdir.load

sudo ln -s ../mods-available/userdir.conf

All done! Now restart Apache via:

sudo apache2ctl restart

We can now access the web applications stored in our /home/username/public_html directory via http://localhost/~username/