well im making my first two tiered cake and i was wondering after u insert the dowels into the first layer, do u put like a cardboard divider in between the te cakes or do just put the top tier on top of the bottom cake?

After you insert the dowels, you need to top them with a cardboard. This is what supports the next tier up. Alan

If you plan to stack this cake on site, you can also use the plastic separator plates.