Megan Danielle’s metallic one-shoulder dress on American Idol

Katy Perry’s yellow floral skirt on American Idol

Matchmaker Floral Diamante Skirt by Zimmermann at Saks Fifth Avenue, $1350

Also available at: Neiman Marcus | Net a Porter | Mytheresa | FWRD

Katy Perry’s embellished tank on American Idol

Matchmaker Embellished Tank by Zimmermann at Nordstrom, $330

Also available at: Saks Fifth Avenue | Neiman Marcus | Harrods

Katy Perry’s purple floral earrings on American Idol

Simo Stud Earrings by Éliou at Saks Fifth Avenue, $125

Also available at: Anthropologie

Katy Perry’s green contrast trim skort on American Idol

Rally Wrap-Effect Tennis Skirt by Staud at Saks Fifth Avenue, $165

Katy’s white off-shoulder dress on American Idol

Taffeta Mini Dress by Jacquemus at Neiman Marcus, $659 (was $1465)

Also available at: Mytheresa | Farfetch