I am making a cupcake tower out of three round cake dummies for a wedding next month. I need to cover them in fabric. I want them to look as smooth as possible. The bride doesn't want the square which would make it much easier IMO. I just can not figure out how to get them covered so that there isn't a ton of fabric on the bottom.

What type of fabric are you using? Does it have any Stretch to it??

If the fabric is stretchy you can try using a circle piece of fabric with a half inch hem all the way around the edge. Then run a cord through the hem (starting and ending in the same hole) to create a draw string. The tighter you draw the string the neater is should form onto the dummy.

Can't you just have a fabric the same size as the sides of the dummy without having to overlap on the top & bottom? Then cover the edges with ribbon or something?

This is what I think might work. Take your fabric, and cut it 1" bigger than you need, for the top and bottom of your circle. Glue fabric and over lap it over the edge on the top and repeat for bottom and then put ribbon or cording in the midde, to cover the seam. I hope this makes sense.