Is there any special preparation I need to do to the ribbon before attaching it to a fondant covered wedding cake? What is the best way to attach it fondant around the bottom/center of each tier. Its four tiers. Any information would be great appreciated.

I don't do any special prep. I just use double-sided tape to hold it together.

If you wish to attach it with buttercream or royal icing, cut a strip of Press n Seal and run it along the back of the ribbon so the BC won't show through. You can use wax paper too...some people iron that on...or use double sided tape to attach wax paper ribbon.

I use packing tape to seal mine. It peals very easily down the sides of the ribbon so you can't see it and then I attach it together with some royal icing. For added measure if there are flowers on the cake I put a few over the seam where the ribbon comes together just to hide the seam as well as to help hold the ribbon together.