Okay so you have mown someone's lawn for a free trial offer. Now what? It's simple. Ask them for your business. Many people are happy with your work and want you to organize a regular contract. But they don't tell you.
Why? Well to put it bluntly, Humans are lazy. It is to much work to call you and organize it. That’s why you need to ask for their business. Do it directly after you have mown heir lawn. If they are not present then call them up. It took me a little while to understand this concept when I was getting started.