I would first start with making MySQL applications. If you've done that, then I would first make a MySQL file or a MySQL class to handle the connections, and queueing. :] Then I would make my own template system, something small like I did, or maybe even a Template class like a MySQL class, IF you're at that point of learning PHP. And most importantly, make a config for putting the site title, and current page title, etc.. All these are basically a fundamental in making a CMS in PHP & MySQL.

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VillageIdiot can have my babbies ;d