From this: to this:
This is an older icon. :D Let's start with this base:
Sharpen the picture up to 40. I smoothed his skin a little with the Tear Drop tool.
Now, I went and and colored his cheeks a bit (instead of it being green) by doin this:
Layer: Color: Auto: White Balance (you can probably fiddle around with Curves if you can't do that)
Duplicate your base and set it to Screen opacity at 100.
Make a new layer and put the color #81cbf2, setting it to Burn, opacity 100.
I made another layer and added the color #040c2c, setting it to Screen, 100. Duplicate that layer and set the duplicate to Difference, 60.
Make two new layers and add this color to the first layer: #a4f8e7, opacity at Burn, 60.
For the second layer, add this color: #ffd7cb, Multiply opacity at 20
Duplicate the light blue layer (#81cbf2) and bring it to the top. Set the opacity to 50.
I then added a tiny text brush by joyfulsong:
(It's a white brush, that's why you can't see it. :P ) And that is it! :D