Step 10 To create the Koi carp, I used the help of a plug-in called SymmetryWorks to make the fish scales. You don’t need the plug-in to make them, but it saves a lot of time! You can either download it from artlandia.com/products/SymmetryWorks and follow my settings as shown above, or you can create your own. Then, with your pattern selected, go to Object > Expand.
Step 11 Draw a Koi carp and duplicate the body shape, using one as a mask for the fish scale (Ctrl/Cmd + 7). Colour the other parts with gradient colour. With luck, your Koi carp should look similar to the one here on the right.
Step 12 To make the fish look solid, duplicate its body and fill it with darker blue colour. Next, apply the Mesh tool (U) and, using the same method as described in steps 4 and 7, add an anchor point in the middle, and fill it with white. Click on Opacity in the menu bar and set the blending mode to Multiply in the drop-down menu.