First thing to do is to talk to the farmers. Go to farms that have likely looking areas ( long fencerows, set asides, waterways, small woods, creeks, etc) and ask the farmers. Tell them you are starting out trapping coyotes and his farm looks like it mighht have coyotes Does he see any around? Hear any? If yes, and you get permission- go and walk over his farm for a hour or two. Go a few days after a rain- this makes sign easier to see.
Now stand on the farm and look around. Get the big picture. Ask yourself- if I was a coyote- where would I probally be and where would I go? THis might seem silly- but try it- it works to get yo uthinking like a coyote. Connect the dots. They have to travel. I like to set on the travel ways next to a little cover.
If you get T & PC, there is an article in the March issue detailing how to go about setting up farmlands.