Paper ribbons can be addictive. You will find yourself buying scrapbook papers that coordinate just so you can make these lovely cards.
If you use text weight papers, you will be able to fold them in half and then punch. This will line the designs up across from each other perfectly.
I have found the Fiskars border punches to be rather fragile. They are not meant for anything heavier than a light weight text paper. You can prolong the life of them by placing the heel of your hand on the pivot point and them pressing the lever to punch. Other wise the plastic and the little pin that are the pivot area will break. Sadly most other punches of this type are made pretty much the same way.
I also used various decorative scissors to achieve the look that I wanted. One way to make sure you get an even cut with your scissors is to draw a line on the back of the paper and use that as a guide for your cut.
On the very widest parts I simply punched one long narrow strip and carefully attached them one at a time to the ribbon. That way you can match up the punched designs on either side and not use as much paper which reduces the over weight of the card.