iirc, back 'in the day' ladies often used detachable 'falls' to manifest the beehive look. I'd recommend making the pouf seperate, then attaching it with a decorative hairband or a strip of hair.
The 'pouf' is achieved with curl, then massive back-combing, with the hair smoothed overtop - I remember as a wee toddler, watching my Mom working on hers at the kitchen table before a 'big occasion', after a night in 'soup-can' hair rollers!
GL, it sounds like a fun project.