I need to glue two bases together, regular cardboard ones. I need a clean looking suggestion for the edges. I am covering the board in fondant. Should I wrap it down the sides? I am worried it would get damaged and look crappy. Paper or ribbon? The edges are corrugated so I want to make sure it covers it and is very clean looking. I guess I left this to the last minute...

I use ribbon held on with tacky glue. I use foamcore rather than cardboard but the finished effect should be the same. Cover the board with fondant first, stopping at the edges, then put the base on your turntable and go around the edge with the glue, then attach the ribbon. If your base is taller than your ribbon, go around twice, overlapping the middle so that the edges are completely covered. Set it aside to dry for a couple hours before you put the cake on it.

Texas Rose is correct with the ribbon...it finishes it off well. I have, recently, rolled my fondant all the way over the sides of the base. The trick is to do this a couple of days ahead of time and then set it somewhere safe to dry. It dries hard as a rock!