Here is a Regular, nice, and cool shading tutorial. Note: I will do the rest of the skin. Don't freak out.
I guess we'll start. Please, if there are any confusing steps, inform me, I will try and fix them :3

So, as you can see, there's a skin shading. You can ask permission to use that on my page, it's in my submissions, and I will. . . probably say yes. Then again, this is a tutorial, so back to that.

First, if you didn't do a before tutorial, please look up hue shifting on Youtube, it's really useful, and enhances your skins so much more. :3 Either way, get six different shades, from dark to light for the hair. After that, we'll start!
 
You're going to want to do this on all sides, making it so you don't have to do all of them one at a time. But, you wan the darkest color, and follow the picture above.

Then you do this, taking the next color for your hair. It's pretty simple.

And this is the next step, it looks a bit weird, but trust me, you're doing great. :D

The next to last step on the hair sides. :D

There you go! Now there will be more add-ons, but right now, we're moving on. >:3

This is the top of your head. Well, the skin head. xD

Do this, as it lines up with all the sides of the hair. :D

And you are done with that. Moving on.

Do this as well. You don't want to forget that. ._.

This will be under the head, I used to forget this before, but now I don't because I realized how essential it is. xD

Now to the back. The rest of the hair.

Also, you'll be using the same shading colors as before, that can change if you shade it correctly, it can be diferent colors, and I might add a tutorial on that later.  

There. Almost done with the back.

One more left :D

Aaand there. Done with that, we'll do the add-on later.

This is the hair, it will look like this in shape, and I normally do the layout first before shading it all, as I find it easier.

Then, use the next lighter color and fill in some of the darker spots.

And we are done with that.

Here is the add on on the sides of the hair, it's not necessary but it is pretty, and adds a cooler effect, making it look more awesome.

Here's the next part. :D

So, I'm only showing one side, but you'll be doing it on all sides to make it look right, it's exactly the same.

So, if you want, you can take the light color for your hair, and add it over the lightest color to add more depth.

Here's the front, again, I like doing an overall dark shade first to be able to actually see what I'm doing, then shade.

Then this.

Then this. ( I say "then this" a lot)

And then you are done. Whew. Completely done. I hope you like the tutorial, and it was helpful. :3