You have come a long way, but the skin is a little too yellow, try more of a pinkish hue, that's more natural. And if your wondering about shading the best thing is to remember where your light source is coming from. Right now the shading makes no sense. If the light is on her left (our right) the shadows will fall on her right (our left) that's a basic in art and life. If you need refs sometimes just looking in a mirror and seeing how the light and shadows fall on your skin helps you to understand how they work.