1. Locating your service line: Your service line runs between your meter and usually the hose bib on the front of your house. In most cases it enters you house in the basement or crawl space near the area where the hose bib is.
2. Locating service line test area: Where the service line enters your house there is a shutoff valve and PRV valve. Some are hidden behind a door or sheet rock.
There are different types of turnoff valves.
3. Identify service line material type: To determine the type of pipe your service line in made of, examine the pipe coming into the house prior to the shutoff valve.
The video below will help in determining pipe type.
4. Take a picture of the pipe in the service line test area (pipe prior to the shutoff valve)