Start! is a wizard to get you started with MDriven, read more here.
What do you need now?
Define information ; adding or changing information classes, attributes or associations. Create diagrams to see and document how classes relate.
Define views ; adding or changing perspectives on information. Define user actions ; adding or changing how users interact with the information and views.
You may also merge in models with functionality you want to have.
Once you have started you can Verify that everything is coherent and no errors are found - and then start the Prototyper to interact with your application. At some point you will want to Deploy (publish) your system to the cloud.