Another method I will use after I have sat for a while is to walk and call as I am walking. like the others said, clucks & purrs. Stay away from the loud yelps that everyone else uses. Keep a steady pace. I have had more birds give one gobble because they think I am leaving and they want the hen to know they are there. Once you hear the gobble, get set up and have your gun ready.

Another tip when walking and calling, always look around and be close to a setup spot before you call. When you get that answer and they are close, you don't want to be caught with your pants down.