Before I started cutting lawns I use to drive around with a stump grinder everyday and knock on doors when I came across a stump. I would walk up to the door and say I have done a few stumps in your area and I would ask them if they where interested. I would not shy away from anyone and made eye contact. Within the first minute I could get a feeling if they where interested. I use to remember for every 3 houses or let's say 1 out of 3 I would get a job.
When I got into lawns it was a different story. I handed out flyers what a joke. I knocked on doors still a joke. Best advertising is word of mouth oh ya and advertising in phone book joke.
If they don't know you and they never heard of you good luck. Now if they heard of you or someone recommended you then your half way in the door already.
I also stay humble , don't talk like your the best ever and price right, do a good job and your fine.