I know I'll get 88 flak guns for this, but take my advice: Go hunting and spend a lot of time stalking wild animals or a friend (in the wilderness). Experience tells me that this is one of the best ways to learn how to be the "hunter".
If your friend or the animal notices you, then you have failed. Start over from the place you began. Also, pay very close attention to all of your surroundings. Memorize and create a mental picture in your mind. If there have been any changes, take note and inspect them from afar.
Just some of my ten cents there.
In loving memory of Omeljan Kuzik.