Painting should be done according to the box art as red was the favorite color of the Spartan Army.  However, I deviated from that scheme to go with black and gold.  You see, my son's school (Marian Catholic High School) and my alma mater are better known as the Marian Spartans.  (Our arch rivals, the Bloom Trojans are just down the road)

This is a great figure to polish your skills with flesh tones.  Oils are helpful here to blend together, but with patience, good results with shading using acrylics can be had.  Washes brought out the face under the helmet giving a very nasty stare/battle yell from this guy.  The shield markings are left blank.  My advice would be to stencil off some appropriate heraldry and use frisket paper to mask it.  I believe Osprey did a book on this subject.  The only research you might need is to catch the movie, "The 300 Spartans", on AMC.  It's a classic and I've read that it will be remade due to the trend of recent movies out there.  (Gladiator, the new Sparticus, Troy, Helen of Troy)