Patience, put your self in a good location through scouting and reading the sign, and be able to out wait the deer. Sitting in a stand or blind all day and keeping noise and movement to a minimum is harder than it sounds, especially in bad weather. If you are spot and stalking, slower the better, an old army sniper who was also one of the best deer hunters I knew always said take two steps, stop-look-listen, repeat, I don't know how many deer I have had come running right by me when creeping through the timber this way that would have made me if I was going faster.