First things first, WAHOOOOOOOOOO. Thank god turkey season is here.
A mouth call is a great tool to use when u can see a tom. Friction call are best for volume. So practice and you'll enjoy using a diaphram. Most turkey dont cross a creek, or any other obstacle in there way they take the path of least resistance so dont count on the creek. I had gobblers hung up over a branch that fell down and they couldnt figure out how to get around it. In the morning use some soft tree yelps to let the tom know your there, and when it gets light do a fly down cackle and imitate a turkey feeding by using purrs and soft clucks. You should always try to positon yourself above a turkey they go up hill in the morning and its hard for them to come down the hill if you in hilly country if its flat set up some decoys so the tom can see where the hens are gathering and hopefully he will come and investigate. So practice your calling and watch some turkey video's good luck and happy hunting.

"ALWAYS LEAVE THE WOODS WITH SOMETHING"