Above the finished result of my mermaid project. 
I also wanted the mermaid to stand out, so below is another version where she isn't surround by much environment. Which do you like best?

 
I'm not good at drawing people by hand so I searched one of the best places around to find stock-art from talented people like Mirish on Deviantart. I found this image and to my imagination this would be the perfect pose for my mermaid.

Her profile: http://mirish.deviantart.com/art/Lost-Fairy-31-322293757
The second step was to make a sketch of how the mermaid should be posed and the surroundings should look. 
Tuning up the surrounding, adding details to her clothing. 
Some more detailing and shading of her body, the water and her fish's tail.
I wasn't satisfied with her black dress so I changed it to red with other curves. Also I added texture to her skin and worked on the shadows. The hair was a challenge too, it didn't worked out the way I want so I remodeld it. 
Texturing the mountains in the water and adding detail to her fish's tail to bring it to live.
Added more color and details to the water and added sparkles to bring the piece to live. 
I hope you like it!
Thank you for watching!