Aww this is nice! She is quite adorable haha! I love what you did with mixing in the greens in with your shading~ that kind of coloring is something that is really going to help your art get noticed one day =) It's something artists(including myself somewhat haha) tend to fail to do: mixing in the colors around the character into the actual character themselves. So make sure not to forget that! Mixing colors that don't match sometimes can really do wonders ^^
I love her pose~ it's almost like she's surfing(the web haha) or flying~ the hard-disk-like symbol on her face is nice too. Haha I love all the little accessories you added!
If there's anything I would say critique-wise..I'd definitely look into studying anatomy more. Although you've got the joints about right, the head is really quite large in comparison to the rest of her body. Perhaps extend the arms out longer and make the hands and bust a bit bigger to balance it out?
Overall, this is great! I wish you luck in the challenge! =)