It does take a lot of practice. I used to be pretty good at it (like many skills, you lose it if you don't use it, and I haven't used it in a while). If you get a topo map of the area you play in, and get out into that area often, using first the map, compass, and your eyes, then just the map and eyes, you will be surprised how you will become able to look at the terrain, then at your map (or the other way around), and know where you are. I hope that sentence makes sense, I'm pooped from a long hard day...