Find a good technical college/trade school and see if you can get into the CNC course if they have one. MasterCam classes are great to help you learn the art of fast programing.
First, you have to learn enough about machining to determine what tools work best for various tasks. If you don't know when something is going right you will not notice when it goes wrong (till it's too late).
Then you have to learn the CNC way to do it. That would be the programming, the setups, the CAD.