A Dancer is good at attacking and weakening multiple enemies. A Dancer has little defense, but when protected by a team, Dancer can unleash great powers.
The dancer and musician are opposite occupations. Unlike the musicians who help their peers in power enhancing, the dancers confuse the enemies' mind by their glamorous dances and interfere with the enemies' actions. The one similarity of the dancers and musicians is that the dance performance can't be interrupted and stopped as well, and the dances also encourage their peers.
Speak to Busker Biff in Placid Plain (X:295 Y:240). He will ask you to repair some Dilapidated Dancewear for his friend Hannah the Dancer. Go to Granny June the Seamstress at X:168 Y:483 in Placid Plain and ask her to repair the Dancewear.
She will require certain ingredients but will give you the list for 100 gold. When you have the Tailoring Materials List, give her 1 Wild Hide and 1 Down so she can start repairs. After 1 minute, give her the Gown Receipt to collect the Glamorous Gown and return to Busker Biff to receive the qualification.