Firstly, downloading SoapUI will help you a lot, when you create a new project there and import that URL, you will see namespaces and method names properly. For the Soap action; for each operation there is 1 soap action. From that link first you should find the operation which you want to use then you will see soap action of that operation.
http://www.c-sharpcorner.com/UploadFile/88b6e5/how-to-call-web-service-in-android-using-soap/
Here, there is a tutorial about creating soap objects etc.