First composition sketch, made with my touch pad (yes).

Second sketch, still very rough but everything is pretty much decided at this point.

Detailed sketch. Added more butterflies to balance a bit the composition.

Linework, slightly sketchy with a textured brush.

Flats + gradients. My fav step because it starts looking nice as soon as the gradients are there.

Shading. For this series of illustrations, I'm picking the colors myself, no layers mode help.

Added lights and some color variations (blue tinted details) + a good level correction in PS and it's done!