Here you can test the WNS.
The first thing you have to do is to register a SingleUser. In the form there are several protocol elements, e.g. SMS, delete the not needed elements!
After register a SingleUser your response contains a user ID. Now you can send a message to the user, just insert the user ID in the notification form an edit the example text to your text.
You can now also edit the SingleUser or register a new Singleuser and then register a Multiuser.