If you can scout before the hunt find the roost and watch where they go. Find the roost and the strut zone and you will be in very good shape.I have had the most success at the roost and the strutting area.
I usually hunt Colorado, the turkeys there roost on the east or south sides of hills, gullies etc. Not sure if thats true in Texas.
I would start high walking ridges using locater calls and looking for sign, they will come to water during the day also. I have a slate call but never use it I prefer glass or mouth calls. Mouth calls are great if you need to call with your gun on a turkey. As far as 4 wheelers go I think if you know where the turkeys are and you keep the 4 wheelers a ridge away you will be fine.
Metal stakes? I have the plastic stakes that come with decoys and I added metal tent stakes that look like nails. I don't hammer them I just shove them in the ground, I would not hammer them.

Good luck and have fun!!