While CNC is inherently complex, a central goal of the Shapeoko project has always been to simplify it and make it accessible.
It should be pretty straight-forward, esp. since as @Adam_Xett noted the files open as closed paths in Carbide Create.
- open file in Carbide Create http://docs.carbide3d.com/assembly/carbidecreate/userguide/
- verify dimensions
- enter stock size and determine desired point of origin
- determine feed and speed rates, either using a calculator, a test cut, or a chart: http://docs.carbide3d.com/support/#tooling-support
- select the geometry and apply appropriate toolpaths
- preview the cut in the app
- save the file
- open Carbide Motion http://docs.carbide3d.com/assembly/carbidemotion/userguide/
- home the machine http://docs.carbide3d.com/tutorials/tutorial-homing/
- load the endmill
- clamp the stock
- set the zero relative to the stock
- load the file
- run it
- watch the machine per http://docs.carbide3d.com/general-faq/machine-operating-checklist/
The prototypical first project is to make a coaster: Let's make a coaster and there are a number of tutorials including an alternate take on a coaster there.
There’s a bit more written up at: https://www.shapeoko.com/wiki/index.php/Workflow