How do you get rid of Junk mail and Flyers on your porch?

Tired of getting my porch littered with business advertisements everyday. It used to be an occasional thing, but over the years it has gotten really worse. No I dont want cleaning services, I don't want to join your church and I definitely don't want to sell my house! I haven't looked at putting a 'not solicitating' or 'no trespassing' sign, but has anyone had success with this? Any other suggestions to get this to stop? TIA!