Add a creature
I always think a portrait painting should have elements that insinuate a greater narrative in the scene and enliven the context. For this piece, I insert a little deep sea creature into the environment to accompany the mermaid.
To complete my mermaid I use the Liquefy function to adjust the shape and detail, and then I tweak the colour balance. Finally, I import the image into ArtRage to apply some subtle oil paint highlights. And now my painting is finished… or perhaps I should just say, “Fin!”