I am a new user.  
Is there a way to access and use guidelines similar to ones in G-Sketchup?  For instance I want to “Create Terrain Perimeter “ to reflect a jog in the actual lot line.  I want to “breakline” at 280’ on a 325’ line so I can reflect the jog but have no marker or indicator as to where 280’ feet is.  I can use “manual dimension” but any mark disappears when I let go of the mouse to go to the “line break” tool.  I assume I am missing a very simple tool or process but so far no luck in finding it.