If your having trouble drawing a person, think about the shape of the eye first. This way you get a realistic look to who it might become! O my goeh this is the most helpful thing ever with anime eyes :D
My latest robot is a bit more complex and cinematic. I used the same toolset as before and sculpted the base forms and all hard surface shell in ZBrush. I did a bit of texturing in Mari and finally got all assets ready for rendering in Keyshot.