This tutorial shows how to add Gen. 6 Exp. All system to Fire Red and attach it to a key item that enables or disables it. It is based on existing tutorials with the few errors or bugs patched and puts together various pieces of info to have it grouped in one single tutorial. For the purpose of this tutorial the item will be the Exp. Share.
The first thing you need to do is find around 420 bytes of free space. Not all is needed but it is better to be safe than sorry.