Take a screen shot using an emulator, download the grid template, isolate what you want to make from the screen shot, use photoshop, stick your pic behind the grid, drop the opacity on the grid, resize the original pic so it fits on the grid, then use the paint bucket tool to fill up each little square with the appropriate colors.
Time consuming method, works best with uncomplicated 8bit sprites, be sure to use basic colors.
More info here: www.animalxing.com





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