I'm making my first "non-family" cake. And I want it to be PERFECT. This order came from a wedding planner. So if it is perfect, there's more down the road. 
Anyways. I've made 4 tiers (8, 10, 12, 14) Alternating Chocolate MMF and Ivory MMF.
But how do I attach the ribbon. It is fabric ribbon, I've heard of chocolate fondant leaking through, does MMF do that too? How do I prep the ribbon? How do I attach it?
Should I attach it pre-stacking, or on-site to ensure it is straight.
Eeks...This is stressful, and totally fun at the same time! 
I cant help you except to say that you should attach it on site .
i would attach the ribbon at the site, you could just use a couple dots of royal here and there to attach it. i don't know about it leaking through. hopefully someone else would have some thoughts.
Here's a link to a previoius discussion about this. I haven't done it; but it looks like a lot of people use wax paper under the ribbon
http://www.cakecentral.com/cake-decorating-ftopict-42189-attaching.html+ribbon
I would just attach in the back. I did this with the red heart cakes in my pics (the ones next to the horrible rainbow brite wedding cake lol) and they stayed on fine. I probably wouldn't moisten them just because it might cause noticible spots on the ribbon.
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