How can i make the andy warhol painting of marilyn monroe on Adobe Photoshop?

I want to make the painting of marilyn's multiple faces in different colors.How can i make the andy warhol painting of marilyn monroe on Adobe Photoshop?
in photoshop open image, use posterize to color limited colors,


http://www.creativepro.com/article/photo…





or apply map with gradient,


http://www.krishnamoorthi.com/2007/01/30…





or use Image%26gt; Adjustment%26gt; variations to adjust color to extreme


http://www.graphic-design.com/Photoshop/…





or adjust saturation level, and add contrast, or threshold or duotone,


http://commons.wikimedia.org/wiki/Image:…


http://commons.wikimedia.org/wiki/Image:…


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