My favorite time is a very narrow window where the snow is about 90% gone except the hard packed trails. The snow gets packed hard and melts slower, so the trails they use the most stand out. Look for trails with a lot of droppings on them. Those are generally the ones from the food sources. Transition lines are always a good bet. Look for transitions from field to trees or even from two different kinds of trees. An example would be where an older logging cut butts up against old growth forest. Deer love to travel transition lines in the terrain/vegetation like that. Sides of valleys and the bottoms. Wind swept hill tops. Thermal cover like big spruce trees in an otherwise deciduous forest.....
I hope you're not in my area. I'm giving up all my secrets!