I use a 3" auger and go 12-18" deep at a 45 degree angle on dirt holes. The deeper you go, the more the coyote has to work the set. And, the longer he's working the set, the more opportunities that you have for him to step on your trap pan.

Everyone has different methods that work, sometimes a 'V' shape formation has natural blockers on the right side and I'll set a trap on the left. I try to setup where the dog gets funneled into an area, spots that already have a natural 'V'. I've used a 'Y' shaped dead fall log over a dirt hole to funnel a coyote onto a trap and it worked well.

Either side is as good as the other on what side of the dirt hole. Roundabout 6-9" in front and 2-3" to the right or left is the target zone. I've welded Expand a pans on my K9 Xtreme's to get a bigger pan for the dog to step on. It's hard to say whether it helped or triggered a bunch of sprung traps because the heavy rains have been so frequent around here.