Yea, I made a little ID card that I got on my shirt/jacket whatever, looks legit.
And SMILE!
Just be a general nice guy, sure, some people just have that quality, some don't but it really helps to get the trust of the customer.
Mine goes like this :
Hi, I'm from GQC Window Cleaning, and we are looking for new customers in this area, I was wondering if you'd like a regular window cleaner. etc etc
Real easy, once you get the first new customer, your up in the clouds.