There are basically five elements to a CNC Project:
Design - thinking and planning what you want to build
CAD - translating it into the computer
CAM - converting it into machine language
Controlling - directing your machine's motion
Machining - building the part to specifications
These five elements are really the building blocks to a CNC project. As you see them above, that is generally the order people associate them in. For example, you can't control until you have a design. You can't use your CAM software before your CAD software. One of the main things you need to address is how these elements interact with each other. The more you use these elements with one another,the more their order will become second nature.