Generally, background dancers for Kpop stars must have a strong foundation in dance, with experience in various styles including hip-hop, contemporary, and Kpop choreography. They should also have a good sense of rhythm, coordination, and stamina, as well as the ability to learn new choreography quickly.
In terms of the audition process, dancers are typically required to submit an application form, a video of their dance skills, and a photo. If their application is successful, they will be invited to attend an audition where they will be evaluated based on their dance skills, appearance, and personality.