Great start! Just remember, don't think of painting the skin and eyes themselves. Think of them as shapes and areas of color, and that makes it easier. Think also about the 3D form of your subject, and how light and shadow fall on it. That's probably not very helpful advice, but also watching people speedpainting with ArtRage on YouTube can be a good way to learn. Good luck and have fun!
~Scribbles
Every artist dips his brush in his own soul, and paints his own nature into his pictures.
~ Henry Ward Beecher