The CAS challenge is a sketch, ofcourse I love that, being part of a sketch team, LOL
But the Make it colourful challenge is coloring skies!!
Withe the new tutorial of Zoe, that should be eaasy, as her tutorials are just great!
But I don't have that one yet, so I had to try without :-D
I combined the sketch and CAS challenge in one card:
Image is colored with copics, the background/sky of the circle is done with PanPastel and an eraser.
The big background is made with Gelatos, and a cloud stencil.