During the conception, I'll frequently begin the process by writing rather than drawing. I'm the type of person who likes organisation, timelines and routine. Rather than start with all the freedom in the world, I prefer to give myself boundaries. There's a saying, "the narrower the stream, the faster the current," and it certainly applies to my process.
I began by making a list of underwater creatures so I could remember different methods of moving and surviving underwater. Then I made a list of what the city could be like. This led me to the concept of a coral city. There could be multiple blowholes to keep the coral wet.. I thought it would be unique to have a shelled creature with blowholes, and the shell's jagged edges could create docking areas.
At this point I had a good idea of how I wanted the creature to look so I decided to start sketching. I was going to have to do an additional illustration from above the water so I firstly focused on what the silhouette would be from above. I instantly liked the feel of having the creature wide at the front and narrowing towards the back with sets of flippers that diminished in size. The creature is meant to have a lot of air in it for buoyancy, and so at one point I was considering more of a jellyfish-type body. Whilst that concept would have made the end of the creature more interesting, it would have been far less interesting from above the water. I therefore decided to go with a tail-end that was more like a tadpole, which I felt made for a more interesting concept (Fig.01).
Next I moved onto making silhouettes of the face. I knew that I wanted the face to be practically part of the body, and be indistinguishable. All of the smaller sketches here were too much like existing sea creatures, and I didn't want this to feel like just a big version of a real-life animal. I therefore had to let a little control go and made a big, black shape, and started carving back into it with a 'scratchy' brush. I really liked the far left profile shot, but it lost character when I tried to transfer it to other views (Fig.02).
At this point, I had to add a step in the process that I don't normally do; I created a three inch high sculpture of the face and visited the local zoo to look at snapping turtles and take reference photos. Due to poor lighting and a surprisingly active turtle, I had to use a fast shutter speed to capture details, and in those dark images I found the mood that I wanted for my illustration. I jumped into the image and tried to capture the idea of all those mounds of flesh and bulging air-filled cavities. I also decided I liked the idea of it swimming around lazily and slack-jawed, and so I decided that it could have giant baleen so that it could have a passive way of feeding. At this point I was working with high opacity brushes for the most part. Then I just hit a couple of parts with the brush on Overlay mode to add some colour variation. I was worried about the image looking too much like a diagram, and so I tilted the horizon in an effort to counteract this (Fig.03 - 06).
For this image I created a custom brush to paint the sky (Fig.07). You can either use the polygonal lasso tool to create a thin diamond, or paint something like Fig.08. Then make a square selection around it and go to Edit > Define Brush Preset. After selecting the brush from the brush presets, go to your brush controls and set the Angle Jitter control to pen tilt. Also activate Other Dynamics. Now you have a calligraphic brush, which is particularly fun to paint skies and the water surfaces. Make sure to save your brush for later use. The brush preview should look like (Fig.09).
As I began working on the underwater part of the image, I created a slightly speckled look by using the Add Noise filter, and a custom brush. To create a brush like the one I used, make a circular selection on a white canvas and go to Select > Feather and choose enough pixels so that it will have a nice, soft edge. Paint the selection completely black. Now select white and set the brush to Dissolve. Lower your opacity and use a soft edged brush to start building up speckles (Fig.10). Now select a normal round brush and change the spacing under the brush tip shape so that there's some space between each circle. Select black and then turn on Scattering and Shape Dynamics. Paint back into your selection to get some bigger black spots. Then select the whole thing and Define as a Brush Preset. Select the brush and turn on Dual Brush and Other Dynamics in the brush controls, and it should paint like (Fig.11). This brush is great for flesh and leather, too.
I decided that I wanted the underwater section to be higher in contrast to really make the creature pop, and create more of a disparity between the above and below water. At this point the team asked me to stagger the flippers vertically, leading the viewer to believe the creature is diving. I believe that it visually looks better after the change, and the confusion may even add some needed drama to the piece. I primarily spent this step adding scales and bumps, and making the city a little more defined (Fig.12).