When drawing a portrait, I like to start out drawing the eyes. The spacing between the eye is the space of one eye in general. Once we have the eyes drawn, we are able to get the nose and mouth placement by ways of measuring vertically from the eye along with angles. Then everything else is just shading.
In general, pretty female faces is harder to draw than male faces. The delicate features of the female face requires a softer touch in shading.
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