Turn on Web server and PHP in Apache for Mac OS

In order to use tubekit (http://www.tubekit.org/) on my mac,
I have turn on Web server and enable php in apache.

It's fairly simple; just follow the instruction in [1] and [2].

[Reference]
[1] http://www.macinstruct.com/node/112
[2] http://osxdaily.com/2012/09/10/enable-php-apache-mac-os-x/