first off, find out what your state laws are about snaring,
then find the trails they are using and set your snare 10-12 inches from the ground with a 10-12 inch loop. I don't like crawl unders, because here the dang deer will use them also /ubbthreads/images/graemlins/angry-smiley-055.gif
I like to snare yotes in the snow, I take the truck and drive thru a field that is snow covered and them set the snares in the tire tracks. I also will take my feet and shuffle them to make a trail that goes for a hundred yards and on the way back out the same trail I'll hang snares in the middle of it. I don't get out of the trail, or the yote will step around the snare. not sure about where you are, but here the yotes will follow you in the snow and use your bootprints to walk in. it you ver off a trail they will follow to see what you was doing. good luck and happy snaring,