Halloween // Dooneese costume help

Help! I really want to be Kristen Wiig’s character Dooneese from SNL this year but am having a hard time finding what I need: the right dress and wig. My biggest hang up is the hair. I’m not sure if I should glue a wig onto a swim cap type thing or try to use some kind of headband to create a large forehead. I already have naturally blonde long hair. Any advice is appreciated!!