If you are starting from scratch I would recommend that you use the factory designs and take off the existing upholstery and use it as a pattern. That's what I did. Of course I used a lot thicker foam in it then the factory did.
Makes the cabin kind of a padded cell. Helps keep the screaming of the passengers quiet on the outside of the car so no one will notice.
Cutting out the patterns is easy. Practice with the machine some. Straight lines are pretty difficult to do at first, but if you get the feel of the machine and the material, it isn't really difficult.