Imperfection is important to make things look more realistic. I added damage to the fins, and to add more character to the model I made his face asymmetrical using the deformer and soft selection. I kept the untouched version as a blend shape, just in case I needed to go back to the symmetrical stage. You would typically do this last, but I was just having fun (Fig.05).
For the three-cornered pirate hat, I simply folded a flat, coin shape geometry three ways and pulled the center part up (Fig.06).
For the eyeball, I had two separate pieces of geometry: one for the iris and choroid (which will be textured); the other for the cornea on top (glossy coat). To keep the eye intact, I added a little membrane piece to the socket as well (Fig.07).
At this stage I'd completed the modeling work, so I moved onto un-wrapping the UVs (Fig.08).
I then exported my .obj out to ZBrush (Mudbox would have also worked) to sculpt aging skin and extra details. I used the references I gathered earlier to guide me in this process. Some of my references were even good enough for me to create high-res brushes. Eventually, I baked out the displacement map and the ambient occlusion/cavity map (Fig.09 – 10).