1) I started with 4 inch thick floral foam, found at Michael's or JoAnn's or whatever craft store you have in your neck of the woods. I bought two 36x12x4 inch pieces. Each of those was cut to be 24 inches long (save the extra pieces for the next two levels).
2) Next, the two 24 inch long pieces were tapped together, both down the middle and around the edges so that when I picked it up it didn't fold in half.
3) One of the extra pieces from step-one was used as the second tier, which was 12x12. And the last extra piece was cut down to be 7x7. We cut it as small as we could leaving it big enough to accommodate a 6 inch cake.
4) Next, we wrapped each tier. I used Wilton's Fanci Foil wrap. I was going for a black and silver look so this worked perfectly. I wrapped each tier just like I would a present.
5) After they were wrapped, we glued the black ribbon all the way around.
6) Stack the tiers and TaDa you now have a cupcake tower.
I needed it to accommodate 60 cupcakes and the little cake on top. Since the tower was placed up against a wall I wasn't able to place many cupcakes on the backside so I simply placed them on the table, essentially creating a 4 tier tower. If your building a tower that is to accommodate a cake on the top then I would start with how big the top tier must be and then work down ( I first tried to do it the other way and it wasn't working out)