To access the settings page, click on the Settings  icon on the top right of your dashboard or push the s  key on your keyboard from the home dashboard page

Click on the Services & App Tests  tab

Click on Change Selection button

Select the group & network on which you want to add the test

Click on the + Add Test  button

A modal will pop up like the one shown below

Select whether you are setting up an internal test (testing a service available on your local network) or an external test (testing a service external to your network e.g. a service accessible via the internet)

Next, select the template type. Predefined  templates are available for common services (e.g. dropbox) with limited configurability and can be selected from the Test Template  list. Custom  templates allow you to create a custom test and configure it to your needs. Custom tests also have predefined templates for testing things like iPerf, TelNet, VoIP MOS, and web servers.

Once you are happy with the test configuration, click on Add to save your new test to the test suite.