Persistence. Don't be afraid to come back and call the same field a couple hours later. And again, and again. Coyotes are most active at night. If you have NV or thermal and hunt at night you will be more effective.
Bait helps too. You can use meat scraps, cat food, dog food, etc. If you bait an area for a couple weeks to get them into the habbit of coming to that spot frequently to look for food, that will increase your odds of seeing one when you go out and hunt at that spot.
I look for fields or open areas where I can see them 200+ yards away. But in western WA that's not always possible. I don't have much experience hunting them in thick woods, but I've seen videos of some people doing that.
Coyotes like to frequent housing developments where there's lots of chickens, cats, small dogs, and other things they can snatch for a meal. Hunting around these areas can be productive.....if the homeowners are ok with you hunting them.
Coyotes also frequent farms with chickens/ducks/pigs/goats/sheep/cows, etc. Farmers are usually happy to have a trusted coyote hunter keeping the coyotes thinned out. Farms also usually have fields which are nice to hunt over. This is where I've had my most consistent success.
