Baby, Katy Perry is a firework. And as the singer—mom to 4-year-old Daisy with fiancé Orlando Bloom—turns the big 4-0, allow this look back at her fashion evolution to show you what she's worth.

Katy Perry is ready to light up the stage again like a firework. In fact ... as Katy—who shares daughter Daisy Dove Bloom, 4, with fiancé Orlando Bloom—is also heading back on the road ...