These two originals from Martin’s Mercantile are displayed with a nice bell shape. The skirts drape nicely over the support of a cage and petticoats creating the nice, soft bell that comes out and drops from about the lower calf down.
This is technically a 30s dress but it shows how the skirt backing construction process was well in place. 
If I Had My Own Blue Box: 
I’m glad you posted the 30s dress. Nice to see confirmation for the facing technique earlier!