In ArcMap 10.2 for desktop, I wish to create an editable layer to add a simple shape to. As of right now, I have a basemap layer and my selected basemap. However, since the basemap layer is not editable on its own (via the Editor toolbar), I am unsure of how to proceed to make a square.
My question is: how do I draw a square on my map? I would like to highlight an area by drawing a square to show the outline of it. Do I have to add a layer or shapefile? If so, how do I create a blank, editable layer or shapefile? It seems like there should be a simple method of drawing a polygon but I can't figure out how to.
For further explanation, I would essentially just like to draw a polygon as if I was doing so in Microsoft Paint then change the color of the outline and set the fill color to be transparent.
Edit: I am trying to create a locator map (I already have a separate data frame for it) and I am also relatively new to ArcMap 10.2.