When you create an environment, you specify a traffic filter for that environment. This filter ensures that all traffic reaching the environment - and, by extension, the configuration changes associated with the environment’s version - is intentional.
To send traffic to a specific environment, send requests to your zone that match the pattern specified in your filter. These could be characteristics such as Edge Server IP, Cookie, Hostname, or User Agent.
To make sure requests are reaching an environment, review the Metrics associated with your environment. These metrics will also help you evaluate whether your configuration changes are affecting traffic in the way you expect.