I'm wondering if anyone has tips for cutting and applying fondant ribbon around the base of tiers. I've never done it before, but I need to do it in a few weeks.

HI, roll it out ,not too thin, between 1/8"-1/4". Use a ribbon cutter(fmm or if you have the wilton one, also. Set these cutters to the width you want your ribbon. Cut it really neat. Then roll up on itself. You can lay it on a piece of fun foam, to help you handle it. Of course put a little water around edge of cake. Dust a little powder sugar under your fondant or whatever medium you are using. and then just a little on top of the ribbon piece before you roll it on to itself. ope i have made sense.Of course , start in the back of your cake. Go slowly and it will come out perfect.Good luck

I do it a little different, I start in the front of the cake, and then put a bow to cover the seam! I have done both types - and like both, although I can't use the chocolate clay here in the warm months.

If you grease the cutting wheel with a little shortning first, it makes a cleaner cut.

Fondant ribbon and bow:
http://cakecentral.com/gallery/1467595

Chocolate clay ribbon and bow:
http://cakecentral.com/gallery/1653859