There really isn't any tricks to getting permission. Just a simple stop at a landowners home and asking if they are willing to give you permission to hunt the land is all there is to it. If they say yes, be willing to offer something in return like venison from the deer you kill on their land, or maybe help cutting wood, or mowing any trails can get your foot in the door. Don't demand that they take anything you offer, just put it out there you are willing to give in return for access. If they don't want any gifts or help, then thats a good deal. Leave it at that. But, it doesn't hurt to let them know. If they say no, then be polite and go to the next place down the road. Keep in mind the time of day too. If its a farmer, I like to go and ask before or after harvest time or whenever they are not busy working on the land. Maybe a Sunday or later in the day.
I only hunt on days that end in ' Y '.