Wow! The very first piece of Skye fanart! Thanks! She's one of my favorite characters, too actually. (I'm making a vector drawing of her for the contest right now, and I'm hoping to also get up a Jason X Skye drawing sometime, too. How does that sound for giving Skye some more love? ) You captured her pure, endearing personality perfectly here. ^__^ Her body looks a bit too straight as a whole, but, at the same time, it makes her look younger and even more innocent, so I actually kind of like it for that, too. The color scheme works well, also; those cool colors give a very free, airy feel to the picture. You picked the right colors for her hair, but, the darker tips look a bit too blocky, and don't fade in very smoothly. The there key would be to either make feathered selections when making those tips, or smudge them more for a softer, more natural look.

There really isn't that much to critique as far as shading goes, because you are certainly improving, (especially with how you shaded her legs, her boots, and the clothing folds ) and you'll get even better as you keep practicing. ^^ I just have two small things to point out:
-that shiny spot on her navel looks a bit awkward, how the line suggests that it's going in, but there's a highlight there instead of a shadow. If you want to put a little shiny curve around her belly, you certainly may, (as you've seen how when I color Null, she's glazed like a Krispy Kreme dougnut. XD ) but when you draw the line like that, I'd recomment placing the highlight as a shiny curve just to the outside of where the belly button starts to go in.
-You actually picked the right colors for her hair, but, the darker tips look a bit too blocky, and don't fade in very smoothly. I'd recommend playing around with smudge tools for making the hair look softer. At first I wondered what on God's Green Earth a SMUDGE would do to make something look cleaner, but then I found that they're really useful for making hair look softer.

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My Manga-[link]
Yes, there is no Fate for us
Only those who are swallowed by
Ignorance and fear and miss a step
Fall into the rapid river called Fate
-Bleach, Volume 6

AWW! Masky, this looks AWESOME!!

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"I'll give you this strawberry ifs joo promise to keep it a secret..." - L

oops, talked about the hair twice. X__X I guess I copied instead of pasted.

--
My Manga-[link]
Yes, there is no Fate for us
Only those who are swallowed by
Ignorance and fear and miss a step
Fall into the rapid river called Fate
-Bleach, Volume 6

^^ ~gives massive cookie~ The hair was a big problem for me, so thanks for that.

LOL, Krispy Kreme Null. That makes me hungry XD;

IT'S COLORS OF THE RAINBOW, NOT COLORS OF THE WI-

Sorry, I couldn't tell if you were trying to tie in Pocahontas with Skittles or not.. XD;

Anyway, this looks really good. When I think of wind, though, I can't say I see a lot of green or purple.. but I suppose it works. >_>

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"I mean, I went there and did homework. I HATE THE OUTDOORS.

A FUCKING SQUIRREL ATE MY BAGEL." -Katie

*envisions chibi dougnut figurines of Null, and gets hungry, too.* XD Let's just hope those don't use strategically placed dougnut holes. X__________X

--
My Manga-[link]
Yes, there is no Fate for us
Only those who are swallowed by
Ignorance and fear and miss a step
Fall into the rapid river called Fate
-Bleach, Volume 6

._. You make me jealous. *stomps feet*

For me, wind has always been a very light green to blue color, since it's not exactly the sky, not exactly the earth. I put purple in there for good measure

And I was intermingling Pocahontas and Skittles XD

So they can sell those separately... ... ._o;