docs: update testdata enable explanantion

docs/sources/features/datasources/testdata.md

@@ -17,7 +17,7 @@ This make is much easier to verify functionally since the data can be shared ver
 
 ## Enable
 
-`Grafana TestData` is not enabled by default. To enable it you have to go to `/plugins/testdata/edit` and click the enable button to enable.
+`Grafana TestData` is not enabled by default. To enable it, first navigate to the Plugins section, found in your Grafana main menu. Click the Apps tabs in the Plugins section and select the Grafana TestData App. (Or navigate to http://your_grafana_instance/plugins/testdata/edit to go directly there). Finally click the enable button to enable.
 
 ## Create mock data.