How can I create a low poly figure and color him with another software? I am making it for a friend who will put it in his mmorpg game. We want it somewhat simple.

Look in the Tutorials Forum (or at, blendernation, blenderwiki, otothecleaner or google) for a tut on building low poly character. Export it as DXF or Obj, whatever format your “another software” imports. Find a forum for that “another software” and ask how to color it.