Print this in two pieces and glue the roses on top of the skull for a nice 3D effect.

for Roses:

Print at 100% infill with a layer height of 0.08mm with a base layer of 0.16mm

Swap Instructions:
Start with Black
At layer #6 (0.56mm) swap to Gray
At layer #7 (0.64mm) swap to Purple
At layer #8 (0.72mm) swap to Red
At layer #14 (1.2mm) swap to Orange
At layer #16 (1.36mm) swap to Yellow
At layer #20 (1.68mm) swap to White for the rest.

for Skull:

Print at 100% infill with a layer height of 0.08mm with a base layer of 0.16mm

Swap Instructions:
Start with Black
At layer #6 (0.56mm) swap to Dark Gray
At layer #13 (1.12mm) swap to Gray
At layer #19 (1.6mm) swap to White for the rest.