You need to get multiple copies of the same item to evolve them, usually 6 for rates and 4 for epics. Each stage drops items, most of the evolved require you to do stages more than once

4-12, I used
Gentleman sapphire hair
Bunny Girl
Flower moon cloak
Bunny heels
Peach sweetheart
Bunny headwear
Black Swan earrings
Nikki choker red
Bow bracelet red
Nurse gloves
Rose belt
Gift box
Light of firefly
Memorial Day (balloons)

4-12, I used
Gentleman sapphire hair
Bunny Girl
Flower moon cloak
Bunny heels
Peach sweetheart
Bunny headwear
Black Swan earrings
Nikki choker red
Bow bracelet red
Nurse gloves
Rose belt
Gift box
Light of firefly
Memorial Day (balloons)

Be sure to play with skills, I usually use smile, charm, picky immune, sleep