The basic procedure is to install Apache, PHP and MySQL. Modify your httpd.conf file to include modules for php. The file is very well commented so reading it would help you a lot. YUM would be an excellent tool to install all the three apps you need.
Next step is to test your PHP installation.
Open up a text editor (gedit or anyone you like) and put the following code...save and put the page in the document root folder of your webserver. The extension of the page has to be .php
Open up your browser and point it to the .php file you just saved. You would see a php configuration page and whole host of information.
Go ahead and install mysql. Open up the php page again and half way on the page you might see a section for mysql. If you see that section...it means you have php with mysql API.
Next step would be to actually create test databases that come with mysql and start the mysql service.
so you use phpMyAdmin to administer mysql using a web-based interface.
Hope that helps,