This is a Birchwood Casey Deer target and will show your hits as yellow as seen above. You can order on-line $12 for 2 targets with extra kill zones. Locate it with your favorite search engine.
This one comes in a 2 pack with extra vitals and should last more than one season.
Deer Vitals are outlined. A medium deer will have a 17 to 18 inch deep chest. A large deer will have an 18 to 20 inch chest. By shooting just below the midpoint and tight behind the front leg you are in the heart/lung vitals. Read the article at Chuck Hawkes below. What is missing here perhaps is that if you can see a shape or tuft of hair in the kill zone to aim at then even better, focus on it as your target. Remember, aim small miss small.
http://chuckhawks.com/kill_zone_game_animals.htm