Bucks-larger tracks that tend to leave deeper impressions and often have more of a split toe look to them. If snow you'll see they drag their feet. Bucks often wander in a zig zag fashion when moving about.
Does-tracks smaller often look like a U and with smaller tracks indicating fawns/yearlings with them. Does more of a direct point a to b thing.
Droppings, bucks often scat in a glob or pile. While does scat in single droppings and often while moving. Bucks are chocolate flavoured and does vanilla. Of course this isn't all scientifically proven....just have to taste and see<img src=icon_smile_shock.gif border=0 align=middle>