Today I worked in photoshop on the poster design for the Lego version of Mona Lisa.
I started by opening monalisa.psd. Then I went into the colors layer then used the rectangular marquee tool to select around the individual legos. Then I used the eyedropper tool to select color from the monalisa layer. Then I right clicked on the selection and chose fill with foreground color in the pop out menu. Then I repeated this step to give each individual lego a solid color.