If possible I look for distinguishing terrain characteristics i.e. funnels, saddles, edges, draws, etc. I hunt the big woods alot though and sometimes the areas that I hunt have very little difference, if any, in terrain. So sometimes it may be something as simple as a small ridge that is 6" higher than the surrounding ground that doesn't get as much water on it as the other areas and will typically have a little thicker underbrush than the surrounding areas.These little differences in terrain often make the difference in where the deer choose to travel.