When you get in the woods calling to your birds before season, be careful and don't let them see you! The safest time to move in the presence of a gobbler is when he's behind a tree etc. or his fan is to you, other wise you will probably be seen. Sent is not important. Pattern the birds if you can and don't keep calling to them.

Mouth calls take practice you will gage a lot before you get the hang of it but they are indispensable! Mine is always in my mouth when I hunt and you can combine calling with it and another hand held call to make it sound like you have several hens or a hen and a gobbler.
Good luck, be safe and Ethical