There are several paths you can take, but the basic use case is this:
1) Prototype your Edison + needed peripherals with the Arduino or Mini Breakout, get to your desired development quality
2) Finalize a PCB board or other form factor for your product based on your prototyping work, have it fabricated
3) Move the Edison module into your form factor, test
4) Move the Edison module back into your prototype, debug, fix
5) Repeat steps 3-4 until satisfied your project works
6) Make any necessary changes to the board / form factor (fix bugs, make improvements), send out to fabricate, test
7) Repeat step 5-6 until satisfied with your project's quality
How you perform these steps (who you go to, materials, etc) is typically driven by your budget and timeline. If you're new to board design, try to find something off the shelf and learn first.
Edison has all the necessary FCC certifications to use it in a real product - though anything you add may change your applicability to laws.