Update heos.markdown (home-assistant#14628)

LouiS22 · fabaff · web-flow · commit c49154ad9246 · 2020-09-27T11:33:23.000+02:00
* Update heos.markdown

Clarify where to call that service for noobs.

* Update formatting

Co-authored-by: Fabian Affolter &lt;mail@fabian-affolter.ch&gt;
diff --git a/source/_integrations/heos.markdown b/source/_integrations/heos.markdown
@@ -44,7 +44,7 @@ A connection to a single device enables control for all devices on the network.
 
 ### Service `heos.sign_in`
 
-Use the sign-in service to sign the connected controller into a HEOS account so that it can retrieve and play HEOS favorites and playlists. An error message is logged if sign-in is unsuccessful. Example service data payload:
+Use the sign-in service (go to Developer Tools -> Services and then run the `heos.sign_in` with your username and password. Use the "Fill example data" first, then change it with your data. Check the logs right after, there you should see if the sign-in was successful or not) to sign the connected controller into a HEOS account so that it can retrieve and play HEOS favorites and playlists. An error message is logged if sign-in is unsuccessful. Example service data payload:
 
 ```yaml
 username: "example@example.com"
