(4) Map reference. The map reference should include the sheet name, sheet number, map
series number, and the scale of the applicable map.
(5) Legend. You use a legend only when the situation requires you to include nonstandard
symbols on your overlay.
Figure 1-10. Map overlay with marginal information
(6) Additional information.
Include any additional information that amplifies the
information on the overlay. Again, make this information as brief and simple as possible.