Knock on the doors, be polite, ask for permission. If they give it to you guarantee you will always call before you go in. Always respect the owner and their property. If they turn you down, thank them politely for their time and explain you understand why they would not want people on their land and leave. A lot of times as you are walking back to your car, they will change their mind. But once again, always be respectful even to the landowner who flat out tells you "NO!" and "Get off my property." Usually someone has trespassed and shot livestock when you get that reply. By remaining polite and respectful, they will understand that not all hunters are buttheads.