I just got internet access for now, I hope I can help.
https://www.creationkit.com/index.php?title=Patrol_(Procedure)
https://www.creationkit.com/index.php?search=xmarker&title=Special%3ASearch&fulltext=Search
I am certain we have patrol markers as a tutorial either on CreationKit.com and in here.
I can not verify the pages in this site, that I attempt to read since they haven't worked for ages.
Also; I can't verify anything since I lost mostly all I owned in life to a hurricane, so I am a bit 'down for the count'.
If I come across my notes I will advise you of it, since I did create a mod that handled patrolling.
Try the patrol link (first link), then try the second to give extra clues to help.