Watch the above video and paint the jellyfish twice.
This matters a lot less than you might think. Watercolor is a very organic process and it is important to get used to the techniques rather than trying to produce an exact replica of each of these paintings. Watercolor paints change color quite dramatically depending on how much water you use, so even if you use the same colors the end result may look very different.
These videos were produced before we had the color names printed on the pens. The names have changed slightly but here are the colors we used:
No.10 Sky Blue
No.34 Dark Cyan