draw the draft with pencil. HB would be the best.
Brush up the color roughly. This is for a general image of the light that hits the profile you wanna paint.
paint the face. add some red on it. pay attention to the shadow. this is for setting the different color zone on the face and prepare for the detail.
get the detail done. this is the step that really need to be careful. please do control the water in your brush.
Let dry. Sign your name. Done！^_^